# A=p-prt for r . would you show me how to solve this equation step by step?

## A=p-prt for r

May 15, 2018

$r = \setminus \frac{p - A}{p t}$

#### Explanation:

The idea here is to isolate the prt onto one side of the equation and then solve for r:
$A + p r t = p - p r t + p r t$
$A + p r t = p$ subtract A from both sides
$A - A + p r t = p - A$
$p r t = p - A$ Now that prt is isolated, you can solve for r
Divide both sides by pt (restriction $p t \setminus \ne 0$)
$\setminus \frac{p r t}{p t} = \setminus \frac{p - A}{p t}$
$r = \setminus \frac{p - A}{p t}$