(2x+1）平方+3（2x+1）=0 x平方-18=0

(2x+1）平方+3（2x+1）=0
(2x+1)(2x+1+3)=0
(2x+1)(2x+4)=0
x=1/2,x=-2
x²-18=0
(x+3√2)(x-3√2)=0
x=-3√2,x=3√2
9x²-49=0
(3x+7)(3x-7)=0
x=-7/3,x=7/3
4（2x-1)²-25=0
(2x-1)²-25/4=0
(2x-1+5/2)(2x-1-5/2)=0
(2x+3/2)(2x-7/2)=0
x=-3/4,x=7/4
x²-2x+1=0
(x-1)²=0
x=1
（x-1）²-4（x-1）+4=0
(x-1-2)²=0
(x-3)²=0
x=3

1.X^2-49/9=0--(X+7/3)(X-7/3)=0平方差公式
2.（2X-1）^2-25/4=0--(2X-1-5/2)(2X-1+5/2)=0----(2X-7/2)(2X+3/2)=0平方差
3.(X-1)^2=0
4.(X-1-2)^2=0---(X-3)^2=0