How do you simplify  sqrt 18 - 3 sqrt 8^2?

Oct 24, 2017

$\sqrt{18} - 3 \sqrt{{8}^{2}} = 3 \left(\sqrt{2} - 8\right)$

Explanation:

$\sqrt{18} - 3 \sqrt{{8}^{2}}$

$= \sqrt{{3}^{2} \cdot 2} - 3 \cdot 8$

$= 3 \sqrt{2} - 24$

$= 3 \left(\sqrt{2} - 8\right)$