Sum of Angles in a Polygon

How can learners use algebra to solve a geometry problem? Help learners create an equation that shows the relationship between the number of sides of a polygon and the sum of the interior angles. Students are asked to divide the quadrilateral found in the resource into two triangles. Then recognize that the sum of interior angles for each triangle drawn is 180 degree and the sum of the interior angles for the quadrilateral is 360 degrees. The second polygon is a pentagon, using the same method, number crunchers verify that the sum of the angles is 540 degrees. It is now up to your algebra learners to describe the relationship of the number of sides and the sum of the interior angles with an equation.