Polygons
Section: GeometryBank code: GEO-POLGRE frequency: MediumPro
1. Core Idea
A polygon is a closed figure with straight sides. Everything about its angles follows from one observation:
An n-sided polygon can be cut into (n - 2) triangles by drawing diagonals from a single vertex.
Since each triangle contributes 180 degrees, the interior angles sum to (n - 2) x 180.
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