1.
(3-y)^2=（y-3）^2,所以y=0或2y=y-3,y=-3.
2.
3x^2-(x+2)^2+2x=3x^2-x^2-4x-4+2x=2x^2-2x-4=2（x+1）（x-2）=0,所以
x=-1或2.