6x^2y+2xy-3x^2y^2-7x-5yx-4y^2x^2-6x^2y,
=-7x^2y^2-3xy-7x
其中|x+3|+(y-2)^2=0
即x+3=0,y-2=0
x=-3,y=2
原式=-7*9*4-3(-3)*2-7(-3)=-252+18+21=-213