# Sum of interior angles

Find the sum of the interior angle of:pentagon,15-gon,and 18-gon.

© SolutionLibrary Inc. solutionlibary.com 9836dcf9d7 https://solutionlibrary.com/math/geometry-and-topology/sum-of-interior-angles-1of#### Solution Preview

...e equal to the sum of the interior angle of "m-gon".

Since the sum of interior angle of a triangle is equal to 180 degrees, the sum of the interior angle of a m-gon is equal to number of triangles that can be drawn inside the shape times the sum of interior angle of a triangle (180 degrees).

For example ...