2(3x-2y)-(x-y)+(-x+9y)
=6x-4y-x+y-x+9y
=4x+6y
题目是错的,请核对题目.昂。。。真的错了吖= = 2x+3y=2012,则代数式2(3x-2y)-(x-y)+(-x+9y)=2(3x-2y)-(x-y)+(-x+9y)=6x-4y-x+y-x+9y=4x+6y=2(2x+3y)=2×2012=4024