已知:3(x-y)的平方-5x-2=2x-7y-4,求x-y的值
问题描述:
已知:3(x-y)的平方-5x-2=2x-7y-4,求x-y的值
答
3(x-y)^2-5x-2x+7y-2+4=0
3(x-y)^2-7(x-y)+2=0
(x-y-2)(3(x-y)-1)=0
x-y=2或x-y=1/3