# How do you simplify 2 times the square root of 20?

Sep 11, 2015

$2 \times \sqrt{20} = 4 \sqrt{5}$

#### Explanation:

$\sqrt{20} = \sqrt{{2}^{2} \times 5} = \sqrt{{2}^{2}} \times \sqrt{5} = 2 \times \sqrt{5}$

$\textcolor{w h i t e}{\text{XXX}}$(assuming only principal [non-negative] square roots)

$2 \times \sqrt{20} = 2 \times \left(2 \times \sqrt{5}\right)$

$\textcolor{w h i t e}{\text{XXX}} = 4 \times \sqrt{5}$

$\textcolor{w h i t e}{\text{XXX}} = 4 \sqrt{5}$