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【329770】5.7 用二元一次方程组确定一次函数表达式 同步练习2

时间:2025-02-05 18:07:23 作者: 字数:2919字


 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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、填空题

1.已知直线l1:y=k1x+b1和直线l2:y=k2x+b2

1)当__________时,l1l2相交于一点,这个点的坐标是________.

2)当_________时,l1l2,此时方程组 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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> 的解的情况是________.

3)当_______时,l1l2重合,此时方程组 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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> 的解的情况是______.

2.无论m取何实数,直线y=x+3my=x+1的交点不可能在第________象限.

3.一次函数的图象过点A53)且平行于直线y=3x <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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> ,则这个函数的解析式为________.

二、选择题

1)函数y=ax3的图象与y=bx+4的图象交于x轴上一点,那么ab等于( )

A.4∶3 B.4∶3 C.(-3)∶(-4 D.3∶(-4

2)如果 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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> 是方程组 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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,则一次函数y=mx+n的解析式为( )

A.y=x+2 B.y=x2 C.y=x2 D.y=x+2

3)若直线y=3x1y=xk的交点在第四象限,则k的取值范围是( )

A.k <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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> B. <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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> k1 C.k1 D.k1k <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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>

三、已知y1= <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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> x4,y2=2ax+4a+b

1)求ab为何值时,两函数的图象重合?

2)如果两直线相交于点(-13),求ab的值.


四、已知两直线y1=2x3,y2=6x

1)在同一坐标系中作出它们的图象.

2)求它们的交点A的坐标.

3)根据图象指出x为何值时,y1y2;x为何值时,y1y2.

4)求这两条直线与x轴所围成的△ABC的面积.

五、请你做一做,想一想

1)在直角坐标系中,请你做出一次函数y=112x的图象.

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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)二元一次方程2x+y=11有几组非负整数解,分别是什么?在上述的直角坐标系中,分别描出这些点,它们在一次函数y=112x的图象上吗?方程2x+y=11的其他解呢?

3)一次函数y=112x的图象上任意一点的坐标适合二元一次方程2x+y=11吗?

4)由此,你能得到什么结论?

参考答案

一、1.1k1k2

方程组 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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> 的解为 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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>

即交点坐标为( <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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> )

2k1=k2b1b2,无解

3k1=k2b1=b2,无数组解

2.3.y=3x12

二、(1D 2D 3B

三、(1)若两函数图象重合,需使 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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=1,b=8时,两函数的图象重合.

2)若两直线相交于点(13),则 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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> ,即 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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>

四、(1)如下图

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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)解方程组 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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(3,3)

3)当x>3时,y1>y2,x<3时,y1<y2.

4)可求得B( <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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> 0)C(60),则SABC= <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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> (6 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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= <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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>

五、(1

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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>

  1. 二元一次方程2x+y=116组非负整数解,分别是

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/174/" title="确定" class="c1" target="_blank">确定</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>

以这几组解为坐标的点都在y=112x的图象上,方程的其他解也在这个函数的图象上.

3y=112x图象上任一点的坐标都适合方程2x+y=11.

4)以方程2x+y=11的解为坐标的点都在一次函数y=112x的图象上,反之,函数y=112x图象上任意点的坐标都是方程2x+y=11的解.