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

$x = \frac{a + b}{2}$
$2 x - a = b$
$\textcolor{w h i t e}{\text{XXX}}$adding $a$ to both sides
$\rightarrow 2 x = a + b$
$\textcolor{w h i t e}{\text{XXX}}$dividing both sides by $2$
$\rightarrow x = \frac{a + b}{2}$