# How do you solve sqrtt-4=7 and check your solution?

Feb 16, 2017

$t = 121$
(see below for method of solution and checking)

#### Explanation:

Given $\sqrt{t} - 4 = 7$
Add $4$ to both sides to get
$\textcolor{w h i t e}{\text{XXX}} \sqrt{t} = 11$
Then square both sides:
$\textcolor{w h i t e}{\text{XXX}} t = 121$

To check this solution:
Substitute $\textcolor{red}{121}$ for $\textcolor{red}{t}$ in
$\textcolor{w h i t e}{\text{XXX}} \sqrt{\textcolor{red}{t}} - 4 = 7$

Left Side $= \sqrt{\textcolor{red}{121}} - 4$
$\textcolor{w h i t e}{\text{XXXXX}} = 11 - 4$
$\textcolor{w h i t e}{\text{XXXXX}} = 7$
$\textcolor{w h i t e}{\text{XXXXXXXXXXXX}} =$ Right Side