# How do you solve 5x^2 = 100 by factoring?

Oct 3, 2015

Make the LHS quadratic and RHS = 0

#### Explanation:

$5 {x}^{2} = 100$
${x}^{2} = 20$
${x}^{2} - 20 = 0$
$\left(x + \sqrt{20}\right) \left(x - \sqrt{20}\right) = 0$
$\left(x + 2 \sqrt{5}\right) \left(x - 2 \sqrt{5}\right) = 0$
$x = - 2 \sqrt{5}$ or $x = 2 \sqrt{5}$