Question

Any help will be awesome

Answer 1

`\textit{circumference of a circle}\\\\ C=2\pi r ~~ \begin{cases} r=radius\\[-0.5em] \hrulefill\\ C=23\pi \end{cases}\implies 23\pi =2\pi r\implies \cfrac{23\pi }{2\pi }=r\implies \cfrac{23}{2}=r \\\\[-0.35em] ~\dotfill\\\\ \textit{area of a circle}\\\\ A=\pi r^2 ~~ \begin{cases} r=radius\\[-0.5em] \hrulefill\\ r=(23)/(2) \end{cases}\implies A=\pi \left( \cfrac{23}{2} \right)^2\implies A=132.25\pi`