Answer
$C=R-P$.
Work Step by Step
The given formula is
$\Rightarrow P=R-C$
Add $C$ to each side.
$\Rightarrow P+C=R-C+C$
Simplify.
$\Rightarrow P+C=R$
Subtract $P$ from each side.
$\Rightarrow P+C-P=R-P$
Simplify.
$\Rightarrow C=R-P$
Hence, the answer is $C=R-P$.
