100-(3X+2y)^2 (x+y)^2-10(x+y)+25
问题描述:
100-(3X+2y)^2 (x+y)^2-10(x+y)+25
答
100-(3X+2y)^2
=(10+3x+2y)(10-3x+2y)
(x+y)^2-10(x+y)+25
=[(x+y)-5]^2
=(x+y-5)^2