\(\bf \qquad \qquad \textit{area of a regular polygon}
\\\\\\
A=\cfrac{1}{4}\cdot n\cdot s^2\cdot cot\left( \frac{180}{n} \right)\quad
\begin{cases}
n=
\begin{array}{llll}
\textit{number of sides in a polygon}\\
\textit{a pentagon, has PENTA=5 sides}
\end{array}\\
s=\textit{length of one of the sides}
\end{cases}\)
