# How do you solve \sqrt { 2x + 7} = 7?

Jun 12, 2017

$x = 21$

#### Explanation:

$\sqrt{2 x + 7} = 7$

Since there's a square root sign on the left side and it is rather bothersome, we can square both sides of the equation to get rid of it:

${\sqrt{2 x + 7}}^{2} = {7}^{2}$

$2 x + 7 = 49$

Now, we can subtract $7$ on both sides to isolate $x$:

$2 x = 42$

And now we divide both sides by $2$ to find the answer:

$\frac{\textcolor{red}{\cancel{\textcolor{b l a c k}{2}}} x}{\cancel{\textcolor{red}{2}}} = \frac{42}{2}$

$x = 21$