Respuesta :

Answer:

The solutions are -0.65 and 4.65.

Step-by-step explanation:

3x^2 - 12x = 9

Divide both sides by 3

x^2 - 4x = 3

To make a square with "x^2 - 4x", you need to have a "+ 4" after it so it can be simplified as (x-2)^2.  So add 4 to both sides.

x^2 - 4x + 4 = 7

(x-2)^2 = 7

x - 2 = (square root) of 7

x = 2 (+/-) (square root) of 7.

x = {-0.65, 4.65}

The solutions are -0.65 and 4.65.

hope this helps:)sorry if it doesnt

Answer:

[tex](x-2)^2=7[/tex]

Step-by-step explanation:

We have been given an equation [tex]3x^2-12x=9[/tex]. We are asked to complete the square for the given equation.

We know that when an equation is in form [tex]x^2+bx=c[/tex], then we will add [tex](\frac{b}{2})^2[/tex] to both sides of equation to make a perfect square.

Dividing both sides by 3, we will get:

[tex]x^2-4x=3[/tex]

Add [tex](\frac{b}{2})^2[/tex] on both sides of equation:

[tex](\frac{b}{2})^2=(\frac{4}{2})^2=2^2=4[/tex]

[tex]x^2-4x+4=3+4[/tex]

[tex]x^2-4x+4=7[/tex]

Now, apply perfect square formula [tex]a^2-2ab+b^2=(a-b)^2[/tex]:

[tex](x-2)^2=7[/tex]

Therefore, our required equation would be [tex](x-2)^2=7[/tex].