# How do you solve 2/5sqrt(10x+6)=12?

Feb 14, 2017

$x = 89.4$

#### Explanation:

$\frac{2}{5} \sqrt{10 x + 6} = 12$

As with any equation, we need to isolate $x$.

Isolate the square root first.

$\textcolor{b l u e}{\frac{5}{2} \times} \frac{2}{5} \sqrt{10 x + 6} = \textcolor{b l u e}{\frac{5}{2} \times} 12$

$\textcolor{w h i t e}{\ldots \ldots \ldots \ldots} \sqrt{10 x + 6} = 30 \text{ } \leftarrow$ now square both sides

$\textcolor{w h i t e}{\ldots \ldots \ldots .} {\sqrt{10 x + 6}}^{2} = {30}^{2}$

$\textcolor{w h i t e}{\ldots \ldots \ldots \ldots \ldots} 10 x + 6 = 900 \text{ } \leftarrow$ subtract 6 from both sides

$\textcolor{w h i t e}{\ldots \ldots \ldots \ldots \ldots \ldots \ldots .} 10 x = 894$

$\textcolor{w h i t e}{\ldots \ldots \ldots \ldots \ldots \ldots \ldots \ldots .} x = 89.4$