# How do you solve x^2 - 20 = 0?

Jun 20, 2018

${x}^{2} = 20$

square root both sides

$x = \setminus \pm \sqrt{20}$

$x = 2 \sqrt{5} \mathmr{and} x = - 2 \sqrt{5}$

Jun 20, 2018

$x = \pm \sqrt{20}$

#### Explanation:

Initial equation

${x}^{2} - 20 = 0$

Add $20$ on both sides

${x}^{2} = 20$

Add a square root to both sides

$\sqrt{{x}^{2}} = \pm \sqrt{20}$

Simplify

$x = \pm \sqrt{20}$

Hope that makes sense!