# How do you solve 9(x + 2)^2 - 7 = 0?

Jul 23, 2016

$- 1.118 \text{ or } x = - 2.882$

#### Explanation:

While it is possible to simply and change this into the form $a {x}^{2} + b x + c = 0$, it can be used as it is.

Compare with $5 {x}^{2} = 20 , \text{ "rArr x^2 = 4 " } \Rightarrow x = \pm 2$

$9 {\left(x + 2\right)}^{2} - 7 = 0 \text{ move the constant and divide by 9}$

${\left(x + 2\right)}^{2} = \frac{7}{9} \text{ square root both sides}$

$x + 2 = \pm \sqrt{\frac{7}{9}}$

$x = + \frac{\sqrt{7}}{3} - 2 \text{ or } x = - \frac{\sqrt{7}}{3} - 2$

=$- 1.118 \text{ or } x = - 2.882$