x²-4x-3x+12=1
x²-7x=-11
(x-7/2)²-49/4=-11
(x-7/2)²=5/4
x-7/2=±根号5/2
x=根号5/2+7/2,x= - 根号5/2+7/2
1/2(2x-5)*2-2=0
(2x-5)*2=4
2x-5=-2,2x-5=2
x=3/2,x=7/2
(2x -1)(x-4)=5
2x²-8x-x+4=5
2x²-9x=1
x²-9/2x=1/2
(x-9/4)²=1/2+81/16
x-9/4=±根号113/4
x=(根号113+9)/4 X= (-根号113+9)/4