2x^2+y(x+y)=8 (x+y)=2 x=(2-y) 2x^2-2y-8=0 2(2-y)^2-2y-8=0 2(4-4y+y^2)-2y-8=0|:2 y^2-4y+4-y-4=0 y^2-4y=0 y(y-4)=0 y1=0 y2=4 x1=2-y1=2-0 x1=2 x2=2-y2=2-4 x2=-2 (2;0) и (-2;4)