(3x+2)²-4x²=0
[(3x+2)+2x][(3x+2)-2x]=0
(5x+2)(x+2)=0
所以有:
x=-2/5 或 x=-2
(3x+2+2x)(3x+2-2x)=0
(5x+2)(x+2)=0
x=-2/5或x=-2
9x^2+12x+4-4x^2=0
5x^2+12x+4=0
(5x+2)(x+2)=0
所以x=-5/2或x=-2
(3x+2)²-4x²=0
[(3x+2)+2x][(3x+2)-2x]=0
(5x+2)(x+2)=0
x= -2/5或 -2