已知2x+y=0,求x-2y分之x-y的值,要过程!
问题描述:
已知2x+y=0,求x-2y分之x-y的值,要过程!
答
2x+y=0
则y=-2x
则(x-y)/(x-2y)
=3x/5x
=3/5