Question

用因式分解法解下列方程

用因式分解法解下列方程
1.25X的平方-1=0
2.x(x-3)+(x-3)=0
3.4x(x-3)=3x-9
4.(2m+1)的平方+3（2m+1）+2=0
急啊

Answer 1

25x^2-1=0
(5x+1)(5x-1)=0
x=-1/5,x=1/5

(x+1)(x-3)=0
x=-1,x=3

4x(x-3)=3(x-3)
(4x-3)(x-3)=0
x=3/4,x=3

(2m+1)^2+3(2m+1)+2=0
(2m+1+1)(2m+1+2)=0
(2m+2)(2m+3)=0
m=-1,m=-3/2

Answer 2

1.25x^2-1=0
(5x)^2-1^2=0
(5x+1)(5x-1)=0
x1=1/5,x2=-1/5

2.x(x-3)+(x-3)=0
(x+1)(x-3)=0
x1=-1,x2=3

3.4x(x-3)=3x-9
4x(x-3)+9-3x=0
4x(x-3)-3(x-3)=0
(4x-3)(x-3)=0
x1=3/4,x2=3

4..(2m+1)的平方+3（2m+1）+2=0
令 2m+1=t
t^2+3t+2=0
(t+1)(t+2)=0
t1=-1,t2=-2
2m1+1=-1,2m2+1=-2
m1=-1,m2=-3/2

Answer 3

1（5x-1）（5x+1）=0
x1=1/5,x2=-1/5
2.(x+1)(x-3)=0
x1=-1,x2=3
3.(4x-3)(x-3)=0
x1=3/4,x2=3

Answer 4

1.25X的平方-1=0
（5x-1)(5x+1)=0
x=1/5 x=-1/5
2.x(x-3)+(x-3)=0
(x-3)(x-1)=0
x=1 x=3
3.4x(x-3)=3x-9
4x(x-3)-(3x-9)=0
4x(x-3)-3(x-3)=0
(4x-3)(x-3)=0
x=3/4 x=3
4.(2m+1)的平方+3（2m+1）+2=0
(2m+1+1)(2m+1+2)=0
m=-1 m=-3/2

Answer 5

1 (5x+1)(5x-1)=0
x=-1/5或1/5
2 (x-3)(x+1)=0
x=3或x=-1
3 (4x-3)(x-3)=0
x=3/4或x=3
4 (2m+1+1)(2m+1+2)=0
m=-1或-3/2