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【330876】人教版第15章 分式 测试卷(3)

时间:2025-02-11 18:53:07 作者: 字数:31722字

15 分式 测试卷(3

一、选择题

1.遂宁市某生态示范园,计划种植一批核桃,原计划总产量达36万千克,为了满足市场需求,现决定改良核桃品种,改良后平均每亩产量是原计划的1.5倍,总产量比原计划增加了9万千克,种植亩数减少了20亩,则原计划和改良后平均每亩产量各多少万千克?设原计划每亩平均产量x万千克,则改良后平均每亩产量为1.5x万千克,根据题意列方程为(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =20 B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =20

C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =20 D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> + <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =20

2.张三和李四两人加工同一种零件,每小时张三比李四多加工5个零件,张三加工120个这种零件与李四加工100个这种零件所用时间相等,求张三和李四每小时各加工多少个这种零件?若设张三每小时经过这种零件x个,则下面列出的方程正确的是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

3.九年级学生去距学校10km的博物馆参观,一部分学生骑自行车先走,过了20min后,其余学生乘汽车出发,结果他们同时到达.已知汽车的速度是骑车学生速度的2倍,求骑车学生的速度.设骑车学生的速度为xkm/h,则所列方程正确的是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> ﹣20 C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> + <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> +20

4.岳阳市某校举行运动会,从商场购买一定数量的笔袋和笔记本作为奖品.若每个笔袋的价格比每个笔记本的价格多3元,且用200元购买笔记本的数量与用350元购买笔袋的数量相同.设每个笔记本的价格为x元,则下列所列方程正确的是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

5.为迎接“六一”儿童节,某儿童品牌玩具专卖店购进了AB两类玩具,其中A类玩具的进价比B类玩具的进价每个多3元,经调查:用900元购进A类玩具的数量与用750元购进B类玩具的数量相同.设A类玩具的进价为m/个,根据题意可列分式方程为(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

6.某工厂现在平均每天比原计划多生产50台机器,现在生产600台机器所需时间与原计划生产450台机器所需时间相同.设原计划平均每天生产x台机器,根据题意,下面所列方程正确的是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

7.某商店销售一种玩具,每件售价90元,可获利15%,求这种玩具的成本价.设这种玩具的成本价为x元,依题意列方程,正确的是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =15% B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =15% C90﹣x=15% Dx=90×15%

8.关于x的分式方程 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> +3= <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 有增根,则增根为(  )

Ax=1 Bx=﹣1 Cx=3 Dx=﹣3

9.甲乙两地相距420千米,新修的高速公路开通后,在甲、乙两地行驶的长途客运车平均速度是原来的1.5倍,进而从甲地到乙地的时间缩短了2小时.设原来的平均速度为x千米/时,可列方程为(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> + <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =2 B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =2

C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> + <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

10.甲种污水处理器处理25吨的污水与乙种污水处理器处理35吨的污水所用时间相同,已知乙种污水处理器每小时比甲种污水处理器多处理20吨的污水,求两种污水处理器的污水处理效率.设甲种污水处理器的污水处理效率为x/小时,依题意列方程正确的是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

11.已知AC两地相距40千米,BC两地相距50千米,甲乙两车分别从AB两地同时出发到C地.若乙车每小时比甲车多行驶12千米,则两车同时到达C地.设乙车的速度为x千米/小时,依题意列方程正确的是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

12.若关于x的分式方程 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> + <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =2有增根,则m的值是(  )

Am=﹣1 Bm=0 Cm=3 Dm=0m=3

13.某次列车平均提速vkm/h,用相同的时间,列车提速前行驶skm,提速后比提速前多行驶50km.设提速前列车的平均速度为xkm/h,则列方程是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

14.小明上月在某文具店正好用20元钱买了几本笔记本,本月再去买时,恰遇此文具店搞优惠酬宾活动,同样的笔记本,每本比上月便宜1元,结果小明只比上次多用了4元钱,却比上次多买了2本.若设他上月买了x本笔记本,则根据题意可列方程(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =1 B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =1 C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =1 D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =1

15.甲、乙两人加工一批零件,甲完成120个与乙完成100个所用的时间相同,已知甲比乙每天多完成4个.设甲每天完成x个零件,依题意下面所列方程正确的是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

16.从甲地到乙地有两条公路,一条是全长450公里的普通公路,一条是全长330公里的高速公路,某客车在高速公路上行驶的平均速度比在普通公路上快35公里/小时,由高速公路从甲地到乙地所需的时间是由普通公路从甲地到乙地所需时间的一半.如果设该客车由高速公路从甲地到乙地所需时间为x小时,那么x满足的分式方程是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> ×2 B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> ﹣35

C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =35 D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =35

17.今年我市工业试验区投资50760万元开发了多个项目,今后还将投资106960万元开发多个新项目,每个新项目平均投资比今年每个项目平均投资多500万元,并且新增项目数量比今年多20个.假设今年每个项目平均投资是x万元,那么下列方程符合题意的是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =20 B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =20

C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =500 D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =500

 

二、填空题

18.某市为处理污水,需要铺设一条长为5000m的管道,为了尽量减少施工对交通所造成的影响,实际施工时每天比原计划多铺设20m,结果提前15天完成任务.设原计划每天铺设管道x m,则可得方程  

19.制作某种机器零件,小明做220个零件与小芳做180个零件所用的时间相同,已知小明每小时比小芳多做20个零件.设小芳每小时做x个零件,则可列方程为  

20AB两地相距60千米,若骑摩托车走完全程可比骑自行车少用 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 小时,已知摩托车的速度是自行车速度的2倍,求自行车的速度.设骑自行车的速度为x千米/时,根据题意可列方程为  

21.若分式方程 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =2有增根,则这个增根是  

22.若关于x的方程 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>1=0有增根,则a的值为  

23.分式方程 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 的解是  

24.解方程: <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>1= <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> ,则方程的解是  

25.分式方程 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =3的解是  

26.分式方程 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 的解x=  

27.分式方程 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 的解为  

 

三、解答题

28.人教版教科书对分式方程验根的归纳如下:

解分式方程时,去分母后所得整式方程的解有可能使原分式方程中的分母为0,因此应如下检验:将整式方程的解代入最简公分母,如果最简公分母的值不为0,则整式方程的解是原分式方程的解;否则,这个解不是原分式方程的解.”

请你根据对这段话的理解,解决下面问题:

已知关于x的方程 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =0无解,方程x2+kx+6=0的一个根是m

1)求mk的值;

2)求方程x2+kx+6=0的另一个根.

29.解分式方程: <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

30.解方程组和分式方程:

1 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

2 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

 


参考答案与试题解析

一、选择题

1.遂宁市某生态示范园,计划种植一批核桃,原计划总产量达36万千克,为了满足市场需求,现决定改良核桃品种,改良后平均每亩产量是原计划的1.5倍,总产量比原计划增加了9万千克,种植亩数减少了20亩,则原计划和改良后平均每亩产量各多少万千克?设原计划每亩平均产量x万千克,则改良后平均每亩产量为1.5x万千克,根据题意列方程为(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =20 B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =20

C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =20 D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> + <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =20

【考点】由实际问题抽象出分式方程.

【分析】根据题意可得等量关系:原计划种植的亩数﹣改良后种植的亩数=20亩,根据等量关系列出方程即可.

【解答】解:设原计划每亩平均产量x万千克,由题意得:

 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =20

故选:A

【点评】此题主要考查了由实际问题抽象出分式方程,关键是正确理解题意,找出题目中的等量关系.

 

2.张三和李四两人加工同一种零件,每小时张三比李四多加工5个零件,张三加工120个这种零件与李四加工100个这种零件所用时间相等,求张三和李四每小时各加工多少个这种零件?若设张三每小时经过这种零件x个,则下面列出的方程正确的是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

【考点】由实际问题抽象出分式方程.

【分析】根据每小时张三比李四多加工5个零件和张三每小时加工这种零件x个,可知李四每小时加工这种零件的个数,根据张三加工120个这种零件与李四加工100个这种零件所用时间相等,列出方程即可.

【解答】解:设张三每小时加工这种零件x个,则李四每小时加工这种零件(x﹣5)个,

由题意得, <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

故选B

【点评】本题考查的是列分式方程解应用题,根据题意准确找出等量关系是解题的关键.

 

3.九年级学生去距学校10km的博物馆参观,一部分学生骑自行车先走,过了20min后,其余学生乘汽车出发,结果他们同时到达.已知汽车的速度是骑车学生速度的2倍,求骑车学生的速度.设骑车学生的速度为xkm/h,则所列方程正确的是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> ﹣20 C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> + <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> +20

【考点】由实际问题抽象出分式方程.

【分析】表示出汽车的速度,然后根据汽车行驶的时间等于骑车行驶的时间减去时间差列方程即可.

【解答】解:设骑车学生的速度为xkm/h,则汽车的速度为2xkm/h

由题意得, <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> + <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

故选C

【点评】本题考查了实际问题抽象出分式方程,读懂题目信息,理解两种行驶方式的时间的关系是解题的关键.

 

4.岳阳市某校举行运动会,从商场购买一定数量的笔袋和笔记本作为奖品.若每个笔袋的价格比每个笔记本的价格多3元,且用200元购买笔记本的数量与用350元购买笔袋的数量相同.设每个笔记本的价格为x元,则下列所列方程正确的是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

【考点】由实际问题抽象出分式方程.

【分析】设每个笔记本的价格为x元,根据“用200元购买笔记本的数量与用350元购买笔袋的数量相同”这一等量关系列出方程即可.

【解答】解:设每个笔记本的价格为x元,则每个笔袋的价格为(x+3)元,

根据题意得: <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

故选B

【点评】本题考查了由实际问题抽象出分式方程的知识,解题的关键是能够找到概括题目全部含义的等量关系,难度不大.

 

5.为迎接“六一”儿童节,某儿童品牌玩具专卖店购进了AB两类玩具,其中A类玩具的进价比B类玩具的进价每个多3元,经调查:用900元购进A类玩具的数量与用750元购进B类玩具的数量相同.设A类玩具的进价为m/个,根据题意可列分式方程为(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

【考点】由实际问题抽象出分式方程.

【分析】根据题意B类玩具的进价为(m﹣3)元/个,根据用900元购进A类玩具的数量与用750元购进B类玩具的数量相同这个等量关系列出方程即可.

【解答】解:设A类玩具的进价为m/个,则B类玩具的进价为(m﹣3)元/个,

由题意得, <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

故选:C

【点评】本题考查的是列分式方程解应用题,找到等量关系是解决问题的关键.

 

6.某工厂现在平均每天比原计划多生产50台机器,现在生产600台机器所需时间与原计划生产450台机器所需时间相同.设原计划平均每天生产x台机器,根据题意,下面所列方程正确的是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

【考点】由实际问题抽象出分式方程.

【分析】根据现在生产600台机器的时间与原计划生产450台机器的时间相同,所以可得等量关系为:现在生产600台机器时间=原计划生产450台时间.

【解答】解:设原计划每天生产x台机器,则现在可生产(x+50)台.

依题意得: <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

故选:A

【点评】此题主要考查了列分式方程应用,利用本题中“现在平均每天比原计划多生产50台机器”这一个隐含条件,进而得出等式方程是解题关键.

 

7.某商店销售一种玩具,每件售价90元,可获利15%,求这种玩具的成本价.设这种玩具的成本价为x元,依题意列方程,正确的是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =15% B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =15% C90﹣x=15% Dx=90×15%

【考点】由实际问题抽象出分式方程.

【分析】设这种玩具的成本价为x元,根据每件售价90元,可获利15%,可列方程求解.

【解答】解:设这种玩具的成本价为x元,根据题意得

 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =15%

故选A

【点评】本题考查由实际问题抽象出分式方程,关键是设出未知数,根据利润率=(售价﹣成本)÷成本列方程.

 

8.关于x的分式方程 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> +3= <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 有增根,则增根为(  )

Ax=1 Bx=﹣1 Cx=3 Dx=﹣3

【考点】分式方程的增根.

【分析】增根是化为整式方程后产生的不适合分式方程的根.所以应先确定增根的可能值,让最简公分母(x﹣1=0,得到x=1,然后代入化为整式方程的方程,检验是否符合题意.

【解答】解:方程两边都乘(x﹣1),得7+3x﹣1=m

原方程有增根,

最简公分母x﹣1=0

解得x=1

x=1时,m=7,这是可能的,符合题意.

故选:A

【点评】本题考查了分式方程的增根,关于增根问题可按如下步骤进行:

让最简公分母为0确定增根;

化分式方程为整式方程;

把增根代入整式方程,检验是否符合题意.

 

9.甲乙两地相距420千米,新修的高速公路开通后,在甲、乙两地行驶的长途客运车平均速度是原来的1.5倍,进而从甲地到乙地的时间缩短了2小时.设原来的平均速度为x千米/时,可列方程为(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> + <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =2 B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =2

C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> + <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

【考点】由实际问题抽象出分式方程.

【专题】行程问题.

【分析】设原来的平均速度为x千米/时,高速公路开通后平均速度为1.5x千米/时,根据走过相同的距离时间缩短了2小时,列方程即可.

【解答】解:设原来的平均速度为x千米/时,

由题意得, <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =2

故选:B

【点评】本题考查了由实际问题抽象出分式方程,解答本题的关键是读懂题意,设出未知数,找出合适的等量关系,列方程.

 

10.甲种污水处理器处理25吨的污水与乙种污水处理器处理35吨的污水所用时间相同,已知乙种污水处理器每小时比甲种污水处理器多处理20吨的污水,求两种污水处理器的污水处理效率.设甲种污水处理器的污水处理效率为x/小时,依题意列方程正确的是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

【考点】由实际问题抽象出分式方程.

【专题】工程问题.

【分析】设甲种污水处理器的污水处理效率为x/小时,则乙种污水处理器的污水处理效率为(x+20)吨/小时,根据甲种污水处理器处理25吨的污水与乙种污水处理器处理35吨的污水所用时间相同,列出方程.

【解答】解:设甲种污水处理器的污水处理效率为x/小时,则乙种污水处理器的污水处理效率为(x+20)吨/小时,

由题意得, <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

故选:B

【点评】本题考查了由实际问题抽象出分式方程,关键是读懂题意,设出未知数,找出合适的等量关系,列出方程.

 

11.已知AC两地相距40千米,BC两地相距50千米,甲乙两车分别从AB两地同时出发到C地.若乙车每小时比甲车多行驶12千米,则两车同时到达C地.设乙车的速度为x千米/小时,依题意列方程正确的是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

【考点】由实际问题抽象出分式方程.

【专题】行程问题.

【分析】设乙车的速度为x千米/小时,则甲车的速度为(x﹣12)千米/小时,根据用相同的时间甲走40千米,乙走50千米,列出方程.

【解答】解:设乙车的速度为x千米/小时,则甲车的速度为(x﹣12)千米/小时,

由题意得, <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

故选:B

【点评】本题考查了由实际问题抽象出分式方程,解答本题的关键是读懂题意,设出未知数,找出合适的等量关系,列出方程.

 

12.若关于x的分式方程 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> + <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =2有增根,则m的值是(  )

Am=﹣1 Bm=0 Cm=3 Dm=0m=3

【考点】分式方程的增根.

【分析】方程两边都乘以最简公分母(x﹣3),把分式方程化为整式方程,再根据分式方程的增根就是使最简公分母等于0的未知数的值求出x的值,然后代入进行计算即可求出m的值.

【解答】解:方程两边都乘以(x﹣3)得,

2﹣x﹣m=2x﹣3),

分式方程有增根,

x﹣3=0

解得x=3

2﹣3﹣m=23﹣3),

解得m=﹣1

故选A

【点评】本题考查了分式方程的增根,增根问题可按如下步骤进行:

让最简公分母为0确定增根;

化分式方程为整式方程;

把增根代入整式方程即可求得相关字母的值.

 

13.某次列车平均提速vkm/h,用相同的时间,列车提速前行驶skm,提速后比提速前多行驶50km.设提速前列车的平均速度为xkm/h,则列方程是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

【考点】由实际问题抽象出分式方程.

【分析】首先根据行程问题中速度、时间、路程的关系:时间=路程÷速度,用列车提速前行驶的路程除以提速前的速度,求出列车提速前行驶skm用的时间是多少;然后用列车提速后行驶的路程除以提速后的速度,求出列车提速后行驶s+50km用的时间是多少;最后根据列车提速前行驶skm和列车提速后行驶s+50km时间相同,列出方程即可.

【解答】解:列车提速前行驶skm用的时间是 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 小时,

列车提速后行驶s+50km用的时间是 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 小时,

因为列车提速前行驶skm和列车提速后行驶s+50km时间相同,

所以列方程是 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

故选:A

【点评】此题主要考查了由实际问题抽象出分式方程问题,解答此类问题的关键是分析题意找出相等关系,(1)在确定相等关系时,一是要理解一些常用的数量关系和一些基本做法,如行程问题中的相遇问题和追击问题,最重要的是相遇的时间相等、追击的时间相等.(2)列分式方程解应用题要多思、细想、深思,寻求多种解法思路.

 

14.小明上月在某文具店正好用20元钱买了几本笔记本,本月再去买时,恰遇此文具店搞优惠酬宾活动,同样的笔记本,每本比上月便宜1元,结果小明只比上次多用了4元钱,却比上次多买了2本.若设他上月买了x本笔记本,则根据题意可列方程(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =1 B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =1 C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =1 D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =1

【考点】由实际问题抽象出分式方程.

【分析】由设他上月买了x本笔记本,则这次买了(x+2)本,然后可求得两次每本笔记本的价格,由等量关系:每本比上月便宜1元,即可得到方程.

【解答】解:设他上月买了x本笔记本,则这次买了(x+2)本,

根据题意得: <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =1

即: <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =1

故选B

【点评】此题考查了分式方程的应用.注意准确找到等量关系是关键.

 

15.甲、乙两人加工一批零件,甲完成120个与乙完成100个所用的时间相同,已知甲比乙每天多完成4个.设甲每天完成x个零件,依题意下面所列方程正确的是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

【考点】由实际问题抽象出分式方程.

【分析】根据题意设出未知数,根据甲所用时间=乙所用时间列出分式方程即可.

【解答】解:设甲每天完成x个零件,则乙每天完成(x﹣4)个,

由题意得, <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

故选:A

【点评】本题考查分式方程的应用,分析题意,找到合适的等量关系是解决问题的关键.

 

16.从甲地到乙地有两条公路,一条是全长450公里的普通公路,一条是全长330公里的高速公路,某客车在高速公路上行驶的平均速度比在普通公路上快35公里/小时,由高速公路从甲地到乙地所需的时间是由普通公路从甲地到乙地所需时间的一半.如果设该客车由高速公路从甲地到乙地所需时间为x小时,那么x满足的分式方程是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> ×2 B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> ﹣35

C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =35 D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =35

【考点】由实际问题抽象出分式方程.

【分析】设出未知数,根据客车在高速公路上行驶的平均速度比在普通公路上快35公里/小时,列出方程即可.

【解答】解:设该客车由高速公路从甲地到乙地所需时间为x小时,那么由普通公路从甲地到乙地所需时间为2x

由题意得, <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =35

故选:D

【点评】本题考查的是列分式方程解应用题,正确设出未知数、找出合适的等量关系是解题的关键.

 

17.今年我市工业试验区投资50760万元开发了多个项目,今后还将投资106960万元开发多个新项目,每个新项目平均投资比今年每个项目平均投资多500万元,并且新增项目数量比今年多20个.假设今年每个项目平均投资是x万元,那么下列方程符合题意的是(  )

A <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =20 B <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =20

C <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =500 D <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =500

【考点】由实际问题抽象出分式方程.

【分析】根据“今后项目的数量﹣今年项目的数量=20”得到分式方程.

【解答】解:今后项目的数量﹣今年的数量=20

 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =20

故选:A

【点评】本题考查了由实际问题抽象出分式方程.找到关键描述语,找到等量关系是解决问题的关键.

 

二、填空题

18.某市为处理污水,需要铺设一条长为5000m的管道,为了尽量减少施工对交通所造成的影响,实际施工时每天比原计划多铺设20m,结果提前15天完成任务.设原计划每天铺设管道x m,则可得方程  <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =15 

【考点】由实际问题抽象出分式方程.

【分析】设原计划每天铺设管道x m,则实际每天铺设管道(x+20m,根据题意可得,实际比原计划少用15天完成任务,据此列方程即可.

【解答】解:设原计划每天铺设管道x m,则实际每天铺设管道(x+20m

由题意得, <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =15

故答案为: <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =15

【点评】本题考查了由实际问题抽象出分式方程,解答本题的关键是读懂题意,设出未知数,找出合适的等量关系,列方程.

 

19.制作某种机器零件,小明做220个零件与小芳做180个零件所用的时间相同,已知小明每小时比小芳多做20个零件.设小芳每小时做x个零件,则可列方程为  <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>  

【考点】由实际问题抽象出分式方程.

【分析】设小芳每小时做x个零件,则小明每小时做(x+20)个零件,根据小明做220个零件与小芳做180个零件所用的时间相同,列方程即可.

【解答】解:设小芳每小时做x个零件,则小明每小时做(x+20)个零件,

由题意得, <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

故答案为: <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

【点评】本题考查了由实际问题抽象出分式方程,解答本题的关键是读懂题意,设出未知数,找出合适的等量关系,列方程.

 

20 AB两地相距60千米,若骑摩托车走完全程可比骑自行车少用 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 小时,已知摩托车的速度是自行车速度的2倍,求自行车的速度.设骑自行车的速度为x千米/时,根据题意可列方程为  <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>  

【考点】由实际问题抽象出分式方程.

【分析】设骑自行车的速度为x千米/时,则摩托车的速度为2x千米/小时,根据骑摩托车走完全程可比骑自行车少用 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 小时,列方程即可.

【解答】解:设骑自行车的速度为x千米/时,则摩托车的速度为2x千米/小时,

由题意得, <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

故答案为: <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

【点评】本题考查了由实际问题抽象出分式方程,解答本题的关键是读懂题意,设出未知数,找出合适的等量关系,列方程.

 

21.若分式方程 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =2有增根,则这个增根是 x=1 

【考点】分式方程的增根.

【专题】计算题.

【分析】根据分式方程有增根,让最简公分母为0确定增根,得到x﹣1=0,求出x的值.

【解答】解:根据分式方程有增根,得到x﹣1=0,即x=1

则方程的增根为x=1

故答案为:x=1

【点评】此题考查了分式方程的增根,增根问题可按如下步骤进行:让最简公分母为0确定增根;化分式方程为整式方程;把增根代入整式方程即可求得相关字母的值.

 

22.若关于x的方程 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>1=0有增根,则a的值为 ﹣1 

【考点】分式方程的增根.

【分析】增根是化为整式方程后产生的不适合分式方程的根.所以应先确定增根的可能值,让最简公分母x﹣1=0,得到x=1,然后代入化为整式方程的方程算出未知字母的值.

【解答】解:方程两边都乘(x﹣1),得

ax+1﹣x﹣1=0

原方程有增根

最简公分母x﹣1=0,即增根为x=1

x=1代入整式方程,得a=﹣1

【点评】增根问题可按如下步骤进行:

让最简公分母为0确定增根;

化分式方程为整式方程;

把增根代入整式方程即可求得相关字母的值.

 

23.分式方程 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 的解是 x=2 

【考点】解分式方程.

【专题】计算题.

【分析】分式方程变形后,去分母转化为整式方程,求出整式方程得到解得到x的值,经检验即可得到分式方程的解.

【解答】解:去分母得:2x﹣1=3x﹣1),

去括号得:2x﹣1=3x﹣3

解得:x=2

经检验x=2是分式方程的解.

故答案为:x=2

【点评】此题考查了解分式方程,解分式方程的基本思想是“转化思想”,把分式方程转化为整式方程求解.解分式方程一定注意要验根.

 

24.解方程: <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>1= <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> ,则方程的解是 x=﹣ <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>  

【考点】解分式方程.

【专题】计算题.

【分析】分式方程去分母转化为整式方程,求出整式方程的解得到x的值,经检验即可得到分式方程的解.

【解答】解:去分母得:4x﹣x+2=﹣3

解得:x=﹣ <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

经检验是分式方程的解.

故答案为:x=﹣ <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

【点评】此题考查了解分式方程,解分式方程的基本思想是“转化思想”,把分式方程转化为整式方程求解.解分式方程一定注意要验根.

 

25.分式方程 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =3的解是 x=3 

【考点】解分式方程.

【专题】计算题.

【分析】分式方程去分母转化为整式方程,求出整式方程的解得到x的值,经检验即可得到分式方程的解.

【解答】解:去分母得:2x=3x﹣3

解得:x=3

经检验x=3是分式方程的解.

故答案为:x=3

【点评】此题考查了解分式方程,解分式方程的基本思想是“转化思想”,把分式方程转化为整式方程求解.解分式方程一定注意要验根.

 

26.分式方程 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 的解x= 1 

【考点】解分式方程.

【专题】计算题.

【分析】本题的最简公分母是x+1,方程两边都乘最简公分母,可把分式方程转换为整式方程求解.结果要检验.

【解答】解:方程两边都乘x+1,得

2x=x+1

解得x=1

检验:当x=1时,x+10

x=1是原方程的解.

【点评】1)解分式方程的基本思想是“转化思想”,方程两边都乘最简公分母,把分式方程转化为整式方程求解.

2)解分式方程一定注意要代入最简公分母验根.

 

27.分式方程 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> = <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> 的解为 x=1 

【考点】解分式方程.

【专题】计算题;压轴题.

【分析】分式方程去分母转化为整式方程,求出整式方程的解得到x的值,经检验即可得到分式方程的解.

【解答】解:去分母得:3x=x+2

解得:x=1

经检验x=1是分式方程的解.

故答案为:x=1

【点评】此题考查了解分式方程,解分式方程的基本思想是“转化思想”,把分式方程转化为整式方程求解.解分式方程一定注意要验根.

 

三、解答题

28.人教版教科书对分式方程验根的归纳如下:

解分式方程时,去分母后所得整式方程的解有可能使原分式方程中的分母为0,因此应如下检验:将整式方程的解代入最简公分母,如果最简公分母的值不为0,则整式方程的解是原分式方程的解;否则,这个解不是原分式方程的解.”

请你根据对这段话的理解,解决下面问题:

已知关于x的方程 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a> =0无解,方程x2+kx+6=0的一个根是m

1)求mk的值;

2)求方程x2+kx+6=0的另一个根.

【考点】解分式方程;根与系数的关系.

【专题】阅读型.

【分析】1)分式方程去分母转化为整式方程,由分式方程无解,故将x=1代入整式方程,即可求出m的值,将m的值代入已知方程即可求出k的值;

2)利用根与系数的关系即可求出方程的另一根.

【解答】解:(1)分式方程去分母得:m﹣1﹣x=0

由题意将x=1代入得:m﹣1﹣1=0,即m=2

m=2代入方程得:4+2k+6=0,即k=﹣5

2)设方程另一根为a,根据根与系数的关系:则有2a=6,即a=3

【点评】此题考查了解分式方程,以及根与系数的关系,解分式方程的基本思想是“转化思想”,把分式方程转化为整式方程求解.解分式方程一定注意要验根.

 

29.解分式方程: <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

【考点】解分式方程.

【专题】计算题.

【分析】分式方程去分母转化为整式方程,求出整式方程的解得到x的值,经检验即可得到分式方程的解.

【解答】解:去分母得:3x=4x﹣4

解得:x=4

经检验x=4是分式方程的解.

【点评】此题考查了解分式方程,解分式方程的基本思想是“转化思想”,把分式方程转化为整式方程求解.解分式方程一定注意要验根.

 

30.解方程组和分式方程:

1 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

2 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

【考点】解分式方程;解二元一次方程组.

【专题】压轴题.

【分析】1)利用代入消元法解方程组;

2)最简公分母为2x﹣2),去分母,转化为整式方程求解,结果要检验.

【解答】解:(1 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

x=﹣2y

代入,得3×(﹣2y+4y=6

解得y=﹣3

y=﹣3代入,得x=6

所以,原方程组的解为 <a href="/tags/4/" title="测试" class="c1" target="_blank">测试</a> <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/846/" title="分式" class="c1" target="_blank">分式</a>

2)去分母,得14=5x﹣2),

解得x=4.8

检验:当x=4.8时,2x﹣20

所以,原方程的解为x=4.8

【点评】本题考查了解分式方程,解二元一次方程组.(1)解分式方程的基本思想是“转化思想”,把分式方程转化为整式方程求解.(2)解分式方程一定注意要验根.