# How do you factor 49x^2-36?

Mar 29, 2018

$\left(7 x + 6\right) \left(7 x - 6\right)$

#### Explanation:

49x^2−36 =
7^2x^2−6^2 =
${\left(7 x\right)}^{2} - {6}^{2} =$
$\left(7 x + 6\right) \left(7 x - 6\right)$
because ${a}^{2} - {b}^{2} = \left(a + b\right) \left(a - b\right)$

Mar 29, 2018

$\left(7 x + 6\right) \left(7 x - 6\right)$

#### Explanation:

Note that $49 = {7}^{2}$ and $36 = {6}^{2}$

So we have ${7}^{2} {x}^{2} - {6}^{2} = {\left(7 x\right)}^{2} - {6}^{2}$.

This is in the form ${a}^{2} - {b}^{2}$ which can be factored to $\left(a + b\right) \left(a - b\right)$

So here we have $a = 7 x$ and $b = 6$, so that would be $\left(7 x + 6\right) \left(7 x - 6\right)$