Question

The radius of this ball is 15 inches. What equation gives the balls surface area in square inches?

Answer 1

$\bf \textit{surface area of a sphere}\\\\ SA=4\pi r^2~~ \begin{cases} r=radius\\[-0.5em] \hrulefill\\ r=15 \end{cases}\implies SA=4\pi 15^2\implies SA=900\pi ~in^2$