若2x+3y=2010,则代数式2(3x-2y)-(x-y)+(-x+9y)=( )

来源:学生作业学帮网 编辑:学帮网 时间:2024/06/17 06:32:48

若2x+3y=2010,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*2010
=4020

2(3x-2y)-(x-y)+(-x+9y)=6x-4y-x+y-x+9y=4x+6y=2(2x+3y)=2×2010=4020