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?_数学解答

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?

人气：164 ℃　时间：2020-03-26 17:09:19

解答

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