Question

Which are steps that could be used to solve 0 = 9(x2 + 6x) – 18 by completing the square? Check all that apply.

18 +81 = 9(x2 + 6x +9)

18+9 = 9(x2 + 6x +9)

18+ 36 = 9(x2 + 6x + 36)

11 = (x + 3)2

1342 = (x + 6)2

799 = (x + 3)2

Answer 1

`18+81=9(x^(2)+6x+9)`

`11=(x+3)^(2)`

Explanation:

we have

`0=9(x^(2) +6x)-18`

Adds 18 both sides

`18=9(x^(2) +6x)`

Complete the square

`18+81=9(x^(2)+6x+9)`

`99=9(x^(2)+6x+9)`

Divide by 9 both sides

`11=(x^(2)+6x+9)`

Rewrite as perfect squares

`11=(x+3)^(2)`