Use the slider to investigate the measure of the angles in each of the regular polygons. Click on the boxes to see the individual angle values and to see the sum within the polygon.
How much does the sum of angles increase with for each additional side? Can you guess a formula that relates the number of sides to the total sum of the angle measures? Extension: What are the measures of the supplementary (known as exterior) angles to the interior angles? Calculate the measures of the exterior angles, then determine the sum of the exterior angles for a polygon with 4, 5, and 10 sides. How does the value of the sum change as the number of sides increases?