(1)分解因式得:(x-3)(x+1)=0,
x-3=0,x+1=0,
x1=3,x2=-1;
(2)2x2-3x-1=0,
b2-4ac=(-3)2-4×2×(-1)=17,
x=
,3±
17
2×2
x1=
,x2=3+
17
4
;3-
17
4
(3)x(2x+3)=4x+6,
x(2x+3)-2(2x+3)=0,
(2x+3)(x-2)=0,
2x+3=0,x-2=0,
x1=-1.5,x2=2;
(4)(2x+3)2=x2-6x+9,
(2x+3)2=(x-3)2,
2x+3=±(x-3),
x1=-6,x2=0;
(5)3x2-6x-2=0,
3x2-6x=2,
x2-2x=
,2 3
x2-2x+1=
+1,2 3
(x-1)2=
,5 3
x-1=±
,
5 3
x1=
,x2=3+
15
3
;3-
15
3
(6)x(x+4)=8x+12,
x2-4x-12=0,
(x-6)(x+2)=0,
x-6=0,x+2=0,
x1=6,x2=-2.