Question

Find the area of a regular pentagon with side equal to 3 and apothem equal to K

Answer 1

a regular polygon has all equal sides.

a PENTA=5, pentagon has 5 sides, so a regular pentagon has 5 equal sides.

$\bf \textit{area of a polygon}\\\\ A=\cfrac{1}{2}ap~~ \begin{cases} a=apothem\\ p=perimeter\\[-0.5em] \hrulefill\\ a=K\\ p=\stackrel{3+3+3+3+3}{15} \end{cases}\implies A=\cfrac{1}{2}K15\implies A=\cfrac{15}{2}K$

Answer 2

The answer is 7.5K :)