因式分解：(x-y)的平方-8(x-y-2)等于?
问题描述：
因式分解：(x-y)的平方-8(x-y-2)等于?
答
(x-y)^2-8(x-y-2)
=(x-y)^2-8(x-y)+16
=[(x-y)-4]^2
=(x-y-4)^2