Sum of Interior Angles of a Pentagon
2013-10-07 07:27
This interactive applet demonstrates the sum of the interior angles of a pentagon. By dragging the horizontal slider, users can observe how the pentagon is divided into triangles. Using the property that the sum of interior angles of a triangle is 180°, it visually derives that the sum of the interior angles of a pentagon is 540°. This helps students understand the geometric derivation of the poly
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