2x+x^2+x^2y^2+2=-2xy
x^2+2x+1+x^2y^2+1=-2xy
x^2+2x+1+x^2y^2+2xy+1=0
(x+1)^2+(xy+1)^2=0
(x+1)^2=0,(xy+1)^2=0
x=-1,xy=-1
-y=-1
y=1
x+y
=-1+1
=0