## Algebra 2 (1st Edition)

$r=\dfrac{(P-2x)}{2 \pi}$
As we are given that, $P=2\pi r+2x$ Subtract $2x$ from each side. The, we have $P-2x=2 \pi r$ Now, divide each side by $2\pi$. The formula for $r$ can be defined as: $r=\dfrac{(P-2x)}{2 \pi}$