问题
解答题
用适当的方法解方程:
(1)x(x-2)+x-2=0
(2)x2-2x=2x+1.
答案
(1)x(x-2)+x-2=0
(x-2)(x+1)=0,
解得:x 1=2,x2=-2;
(2)x2-2x=2x+1
x2-4x+4=1+4,
(x-2) 2=5,
x-2=±
,5
解得:x 1=2+
,x2=2-5
.5
用适当的方法解方程:
(1)x(x-2)+x-2=0
(2)x2-2x=2x+1.
(1)x(x-2)+x-2=0
(x-2)(x+1)=0,
解得:x 1=2,x2=-2;
(2)x2-2x=2x+1
x2-4x+4=1+4,
(x-2) 2=5,
x-2=±
,5
解得:x 1=2+
,x2=2-5
.5