How Do You Calculate Length Of Apothem?
The apothem is distance from the center of a polygon to the midpoint of one of its sides. Only regular polygons have apothems because irregular polygons do not have a center point. All sides are equal lengths in regular polygons. In order to calculate the apothem, you need to know the number of sides and either the radius or the side lengths. Make sure to set your calculator to radians rather than degrees before starting the calculations. Count the number of sides of the polygon. For example, a pentagon would have five sides. Measure the side length. For this example, each side will be seven inches. Divide pi, approximately 3.14, by the number of sides in your polygon. For this example, you would divide pi by 5 and get about 0.628. Use your calculator to calculate the tangent of the result from step 3 in radians. For this example, the tangent of 0.628 equals about 0.726. Multiply the result from step 4 by 2. Continuing the example, you would multiply 0.726 by 2 to get 1.452. Divide the
