(x-1)的平方-(x-1)(x+5)=18求X
问题描述:
(x-1)的平方-(x-1)(x+5)=18求X
答
(x-1)的平方-(x-1)(x+5)=18
x²-2x+1-x²-4x+5=18
6x=1+5-18
6x=-12
x=-2