Respuesta :

Simple....

you have: [tex]3x= \sqrt{12-12x} [/tex]

So...first you know you're trying to find x..

But, you have a square root on one side...to remove this you'd have to square both sides--->>>

[tex](3x)^{2} = \sqrt{12-12x} ^{2} [/tex]

Leaving you with....

[tex] 9x^{2} =12-12x[/tex]

Move the terms over and set it equal to zero.

-->>

[tex] 9x^{2}+12x-12=0 [/tex]

Factor out a 3...

[tex]3( 3x^{2} +4x-4=0)[/tex]

What multiplies to -12 and adds to 4?

6*-2=-12

6+-2=4

Leaving you with...

[tex]3(3x-2)(x+2)=0[/tex]

Remember you're solving for 0....

3x-2=0

3x-2=0
    +2  +2

3x=2

[tex] \frac{3x}{3} = \frac{2}{3} [/tex]

x=
[tex] \frac{2}{3} [/tex]

Then-->>

x+2=0

x+2=0
  -2   -2

x=-2

Thus, your answer.