Question

Find the circumference of a circle that has an area of 452.16 square meters. (Use 3.1416 as the value of π.)

Answer 1

$\bf \textit{area of a circle}\\\\ A=\pi r^2\quad \begin{cases} r=radius\\ -----\\ A=452.16 \end{cases}\implies 452.16=\pi r^2\implies \cfrac{452.16}{\pi }=r^2 \\\\\\ \boxed{\sqrt{\cfrac{452.16}{\pi }}=r}\\\\ -------------------------------\\\\ \textit{circumference of a circle}\\\\ C=2\pi r\qquad \qquad \implies C=2\pi \left( \boxed{\sqrt{\cfrac{452.16}{\pi }}} \right)$

so, is just that product, recall to use "3.1416 as the value of π".