Question

Find the area of the regular decagon if the apothem is 2.8ft and a side is 1.8ft

Answer 1

DECA=10, decagon = 10 sides.

since each side is 1.8 long, all 10 sides will be 10*1.8 or 18 units long, so that'd be the perimeter then,

$\bf \textit{area of a regular polygon}\\\\ A=\cfrac{1}{2}ap~~ \begin{cases} a=apothem\\ p=perimeter\\ ------\\ a=2.8\\ p=18 \end{cases}\implies A=\cfrac{1}{2}(2.8)(18)$