问题
解答题
用因式分解法解下列方程:
(1)(x-1)2-2(x-1)=0
(2)9x2-4=0
(3)(3x-1)2-4=0
(4)5x(x-3)=(x-3)(x+1)
(5)x2-4x-12=0
(6)x2-12x+35=0.
答案
(1)分解因式得:(x-1)(x-3)=0,
可得x-1=0或x-3=0,
解得:x1=1,x2=3;
(2)分解因式得:(3x-2)(3x+2)=0,
可得3x-2=0或3x+2=0,
解得:x1=
,x2=-2 3
;2 3
(3)分解因式得:(3x-1+2)(3x-1-2)=0,
可得3x+1=0或3x-3=0,
解得:x1=-
,x2=1;1 3
(4)方程移项得:5x(x-3)-(x-3)(x+1)=0,
分解因式得:(x-3)(4x-1)=0,
解得:x1=3,x2=
;1 4
(5)分解因式得:(x+2)(x-6)=0,
可得x-2=0或x+6=0,
解得:x1=2,x2=-6;
(6)分解因式得:(x-5)(x-7)=0,
可得x-5=0或x-7=0,
解得:x1=5,x2=7.