# How do you simplify ( 7 + sqrt3 ) (7 - sqrt3)?

Jul 1, 2016

$= 46$

#### Explanation:

you use this idea

$\left(a - b\right) \left(a + b\right)$

$= {a}^{2} + a b - a b - {b}^{2}$

$= {a}^{2} - {b}^{2}$

so you should get

${7}^{2} - {\left(\sqrt{3}\right)}^{2}$

$= 49 - 3$

$= 46$