Question

The area of a circle is 25pi m squared what is the circumference

Answer 1

$\bf \textit{area of a circle}\\\\ A=\pi r^2\quad \begin{cases} r=radius\\ -----\\ A=25\pi \end{cases}\implies 25\pi =\pi r^2\implies \cfrac{25\pi }{\pi }=r^2 \\\\\\ 25=r^2\implies \sqrt{25}=r\implies 5=\boxed{r}\\\\ -------------------------------\\\\ \textit{circumference of a circle}\\\\ C=2\pi r\qquad \qquad C=2\pi\left( \boxed{5} \right)\implies C=10\pi$