若x,y满足等式|x+2|+(y-3)^2=0,则(5x^2 y+5xy-7x)-(4x^2y+5xy-7x)的值为?

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若x,y满足等式|x+2|+(y-3)^2=0,则(5x^2 y+5xy-7x)-(4x^2y+5xy-7x)的值为?
若x,y满足等式|x+2|+(y-3)^2=0,则(5x^2 y+5xy-7x)-(4x^2y+5xy-7x)的值为?

若x,y满足等式|x+2|+(y-3)^2=0,则(5x^2 y+5xy-7x)-(4x^2y+5xy-7x)的值为?
x+2=0
y-3=0
x=-2
y=3
(5x^2 y+5xy-7x)-(4x^2y+5xy-7x)
=5x^2 y+5xy-7x-4x^2y-5xy+7x
=x^2y
=4*3
=12

|x+2|+(y-3)^2=0
所以|x+2|=0 (y-3)^2=0
故x=-2 y=3
所以(5x^2 y+5xy-7x)-(4x^2y+5xy-7x)
=(5x(-2)^2*3+5*(-2*3)-7*(-2))-(4x(-2)^2*3+5x(-2)*3-7x(-2))
=(60-30+14)-(48-30+14)
=12