# How do you simplify 4sqrt6(7sqrt6 - 4sqrt5)?

Mar 7, 2017

You first use the distributive property to work out the parentheses:

#### Explanation:

$= 4 \sqrt{6} \cdot 7 \sqrt{6} - 4 \sqrt{6} \cdot 4 \sqrt{5}$

$= 4 \cdot 7 \cdot \sqrt{6} \cdot \sqrt{6} - 4 \cdot 4 \cdot \sqrt{6} \cdot \sqrt{5}$

$= 28 \cdot {\left(\sqrt{6}\right)}^{2} - 16 \cdot \sqrt{6 \cdot 5}$

$= 28 \cdot 6 - 16 \sqrt{30}$

$= 168 - \sqrt{30}$