Question

用分解因式法解下列方程 [1]x(x+1)-5x-5=0 [2](2x+3)^2-(x-1)^2=0 [3](x+根号3

Answer 1

1.

x(x+1)-5x-5=0

x(x+1)-5(x+1)=0

(x+1)(x-5)=0

x=-1或x=5

2.

(2x+3)²-(x-1)²=0

[(2x+3)+(x-1)][(2x+3)-(x-1)]=0

(3x+2)(x+4)=0

x=-2/3或x=-4

3.

(x+√3)²=4√3x

x²+2√3x+3=4√3x

x²-2√3x+3=0

(x-√3)²=0

x=√3