1)x^2+2(x-1)=6
x^2+2x-2-6=0
x^2+2x-8=0
D=K^2-ac=1+8=9
x1=-1+3=2
x2=-1-3=-4
y1=2-1=1
y2=-5
2)(y-2)y-y=10
y^2-2y-y=10
y^2-3y-10=0
D=b^2-4ac=9+40=49
y1=3+7/2=5
y2=3-7/2=-2
x1=3
x2=-4
3)x(x+2)+x^2=4
x^2+2x+x^2-4=0
2x^2+2x-4=0
D=1+8=9
x1=-1+.3/2=1
x2=-2
y1=3
y2=0