Area of Polygons and Circles
Area formulas can be found at “Reference Table for Areas”
Let’s pick up some hints for those more challenging problems involving area.
Regular polygons have a center and a radius (coinciding with their circumscribed circle), and the distance from the center perpendicular to any side is called its apothem.
The apothem of a regular polygon is a line segment from the center of the polygon perpendicular to any side of the polygon. Triangle DOC is an isosceles triangle, making the apothem the altitude of this triangle and the median of this triangle (going to the midpoint P.) The apothem is also the radius of the inscribed circle.
The apothem can be used to determine area:
Area of Sector of a Circle
