①、x1=1/4x2=-7/5
②、x1=-3/2x2=1/3
③、3x(x-1)=2(1-x)
(x-1)(3x+2)=0
x1=1 x2=-2/3
④、原式=
2(x-3)=(x-3)(x+3)
(x-3)(2x-6+x+3)=0
(x-3)(3x-3)=0
x1=3x2=1