Geometric Construction and Symmetry of a Regular Decagon

This GeoGebra example demonstrates the step-by-step geometric construction of a regular decagon (ten-sided polygon), highlighting its vertices, equal sides, equal interior angles, and reflection symmetry. Core mathematical concepts include regular polygons, polygon symmetry, angle measures, and planar geometric construction. The construction uses the Polygon command to create the decagon object poly1 and the Segment command to draw individual sides such as segments a through j, with points A, B, C through L defining vertices and text1, text2 providing labels. It is suitable for middle school geometry lessons, high school regular polygon investigations, and classroom demonstrations of symmetry and polygon properties.