把(x-y)看做一个因式,将3(x-y)的二次方-7(x-y)+8(x-y)的二次方+5(x-y)合并同类项得 ?

问题描述:

把(x-y)看做一个因式,将3(x-y)的二次方-7(x-y)+8(x-y)的二次方+5(x-y)合并同类项得 ?

原式=(3+8)(x-y)²+(-7+5)(x-y)
=11(x-y)²-2(x-y)