# How do you solve 9n+18=81?

Oct 29, 2016

$\textcolor{g r e e n}{n = 7}$

#### Explanation:

Given
$\textcolor{w h i t e}{\text{XXX}} 9 n + 18 = 81$

Noticing that all the terms are multiples of $9$
we can simplify this by dividing both sides by $9$
$\textcolor{w h i t e}{\text{XXX}} n + 2 = 9$

Now if we subtract $2$ from both sides, we get
$\textcolor{w h i t e}{\text{XXX}} n = 7$