# How do you factor 25u²-49?

Jan 13, 2016

The factorised form is
color(blue)((5u-7)(5u+7)

#### Explanation:

$25 {u}^{2} - 49$

The expression can be written as
${\left(5 u\right)}^{2} - {7}^{2}$

This is of the form :
color(blue)(a^2-b^2 = (a-b)(a+b)

Applying the same:
(5u)^2 -7^2 = color(blue)((5u-7)(5u+7)