3x^2=x+4和(x+3)(x-4)=-6用因式分解法解决,急,

问题描述:

3x^2=x+4和(x+3)(x-4)=-6
用因式分解法解决,急,

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

(x+3)(x-4)=-6
x^2-4x+3x-12=-6
x^2-x-6=0
(x-3)(x+2)=0
x1=3, x2=-2

答:
3x^2=x+4
3x^2-x-4=0
(3x-4)(x+1)=0
x1=4/3,x2=-1
(x+3)(x-4)=-6
x^2-x-12=-6
x^2-x-6=0
(x-3)(x+2)=0
x1=3,x2=-2