合併同類項3(x-y)的平方-7(x-y)+8(x-y)的平方+6(x-y) 3(x-y)的平方-7(x-y)+8(x-y)的平方+6(x-y)急啊

合併同類項3(x-y)的平方-7(x-y)+8(x-y)的平方+6(x-y) 3(x-y)的平方-7(x-y)+8(x-y)的平方+6(x-y)急啊

3(x-y)的平方-7(x-y)+8(x-y)的平方+6(x-y)
=10(x-y)^2