# How do you solve x^2 + 14x + 20 = 0 by completing the square?

Aug 30, 2016

$x = - 7 \pm \sqrt{29}$

#### Explanation:

$1 \left({x}^{2} + 14 x + n - n\right) = - 20$

$n = {\left(\frac{b}{2}\right)}^{2} = {\left(\frac{14}{2}\right)}^{2} = 49$

$1 \left({x}^{2} + 14 x + 49 - 49\right) = - 20$

$1 \left({x}^{2} + 14 x + 49\right) - 49 = - 20$

$1 {\left(x + 7\right)}^{2} = 29$

$\left(x + 7\right) = \pm \sqrt{29}$

$x = \pm \sqrt{29} - 7$

Hopefully this helps!