Interior/Exterior Angles and Angles of Polygons

Interior/Exterior Angles and Angles of Polygons


Students will identify and find missing interior and exterior angles in polygons.

Students will identify, classify, and find missing angle measures in triangles and other polygons.


The sum of the angle measures in triangles and polygons add up to certain amounts while interior and exterior angles add up to 180 degrees.

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Finding the Missing Angles in Triangles

Source: Khan Academy from YouTube

Sum of Angles in Polygons

Source: Khan Academy from YouTube

Interior Angles of Polygons

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Classifying Triangles

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Source: Scott Foresman Math Textbook