(-2xy+2 x+3y)-(3xy+2y-2x)-(x+4y+xy)
=-2xy+2x+3y-3xy-2y+2x-x-4y-xy
=-6xy+3x-3y
=-6*(-2)+3*1
=15
不懂可追问,有帮助请采纳,谢谢!