（x-1）(x+1)=6x
x²-1=6x
x²-6x=1
(x-3)²=10
x-3=±√10
x=3±√10
(x+1)2-3(x+1)-28=0
(x+1-7)(x+1+4)=0
(x-6)(x+5)=0
x=6或x=-5
(2x-3)2=(5x-2)2
(2x-3)²-(5x-2)²=0
(2x-3+5x-2)(2x-3-5x+2)=0
(7x-5)(-3x-1)=0
x=5/7或x=-1/3