The apothem of a regular polygon can be found multiple ways. The area of a regular polygon is half its perimeter times the apothem. An apothem of a regular polygon will always be a radius of the inscribed circle. The word "apothem" can also refer to the length of that line segment. The inradius of a regular polygon is also called apothem. This radius is also termed its apothem and is often represented as "a".