Answer
$11.98$ feet
Work Step by Step
From part b, we found: $15.7x^2=2252.8$
Divide both sides by $15.7$: $x^2=\frac{2252.8}{15.7}$
Simplify: $x=\pm \sqrt \frac{2252.8}{15.7}=\pm 11.98$
Hence, the radius of the pool is about $11.98$ feet