hotalpha
幼苗
共回答了12个问题采纳率:91.7% 举报
(1)移项,两边同除2,得x 2 -2x=5,
配方,得x 2 -2x+1=6,
即(x-1) 2 =6,
两边开平方,得x-1=±
6 ,
即x 1 =1+
6 ,x 1 =1-
6 ;
(2)移项,得2x 2 +3x-4=0,
△=3 2 -4×2×(-4)=41,
∴x 1 =
-3+
41
4 ,x 2 =
-3-
41
4 ;
(3)移项,得)(x-2) 2 -2(x-2)=0,
提公因式,得(x-2)(x-2-2)=0,
解得x 1 =2,x 2 =4;
(4)因式分解,得(
2 x-1)(x+2
2 )=0,
解得x 1 =
2
2 ,x 2 =-2
2 .
1年前
6