(1)3y²-6y=03y(y-2)=03y=0,y=0y-2=0,y=2(2)(1+x)²-9=0(1+x+3)(1+x-3)=0x+4=0,x=-4x-2=0,x=2(3)(x+2)(x+3)=X+3(x+2)(x+3)-(x+3)=0(x+3)(x+2-1)=0x+3=0,x=-3x+1=0,x=-1
3y（y-2）=0y=0y-2=0，y=2
