Where does the exterior angle theorem come from

The video tutorial explains how to calculate the sum of exterior angles in different polygons, including squares, triangles, and octagons. It begins with a discussion on the properties of exterior angles and their relationship with interior angles, emphasizing the concept of supplementary angles. The tutorial demonstrates calculations for a square and an equilateral triangle, showing that the sum of exterior angles is always 360 degrees. It concludes with a detailed example of an octagon, reinforcing the consistent sum of exterior angles across polygons.

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