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【329768】5.7 用二元一次方程组确定一次函数表达式 基础练习

时间:2025-02-05 18:07:15 作者: 字数:1877字


 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>

5.7 用二元一次方程组确定一次函数表达式

一、解答题

1.已知一次函数的图象过点M32 ),N(-1,-6 )两点,求一次函数的表达式.




2.如图一次函数 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a> 的图象经过点A和点B,求一次函数的表达式.

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>

3.在弹性限度内,弹簧的长度 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>cm )是所挂物体质量 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>kg)的一次函数.当所挂物体的质量为3kg时,弹簧长16cm;当所挂物体的质量为4kg时,弹簧长度为16.5cm. <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a> 之间的函数关系式.






4.已知直线 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a> 与直线 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a> 的交点的横坐标为2,与直线 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a> 的交点的纵坐标为7,求直线的解析式.





5.如图,表示小王骑自行车和小李骑摩托车者沿相同的路线由甲地到乙地行驶过程的函数图象,两地相距80千米,请根据图象解决下列问题:

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a> 车行驶过程的函数图象, <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a> 车行驶过程的函数图象.

哪一个人出发早?早多长时间?哪一个人早到达目的地?

早多长时间?

求出两个人在途中行驶的速度是多少?

分别求出表示自行车和摩托车行驶过程的函数解析式,

并求出自变量x的取值范围.

参考答案

1.解:设一次函数表达式为 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>

依题意得: <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>

解得: <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>

答:一次函数表达式为 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>

2.解:依题意得: <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>

解得: <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>

答:一次函数表达式为 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>

3.解:设yx之间的函数关系式为 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>

依题意得: <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a> 解得: <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>

答:yx之间的函数关系式为 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>

4.解:设直线 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a> 的解析式为 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a> ,当 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a> 时, <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a> ,当 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a> 时, <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>

依题意得: <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a> 解得: <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>

答:直线 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a> 的解析式为 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>

5.(1)自行 ,摩托

2)小王早出发,早3小时,小李早到目的地,早3小时

3)小王:10 km/h,小李40 km/h

4)自行车: <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>

摩托车: <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a> <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</a> <a href="/tags/197/" title="基础" class="c1" target="_blank">基础</a> <a href="/tags/380/" title="方程" class="c1" target="_blank">方程</a> <a href="/tags/885/" title="函数" class="c1" target="_blank">函数</a>