# How do you solve for a in x= -b/2a?

Apr 22, 2018

$\frac{2 x}{- b} = a$

#### Explanation:

You have to reverse the mapping, so first multiply both sides by 2 this will remove it from the RHS (right hand side)

$\textcolor{red}{2} x = - \textcolor{red}{2} \frac{b}{\textcolor{red}{2}} a$

$2 x = - b a$

Divide by negative b or $- b$

$\frac{2 x}{\textcolor{red}{- b}} = \frac{\textcolor{red}{- b}}{\textcolor{red}{- b}} a$

$\frac{2 x}{- b} = a$