(1)2x^2-4x+2=x^2-1
x^2-4x+3=0
(x-1)(x-3)=0
x=1或x=3
(2)(y+3)^2-8y=2(y+3)-4(y-1)
y^2-2y+9=-2y+10
y^2=1
y=1或y=-1