Triangle Construction #1: Basic Triangle with Polygon Command

This example demonstrates how to construct a basic triangle in GeoGebra by defining three points A, B, C and using the Polygon command, which automatically generates the triangle's interior (poly1) and its three sides (a, b, c). The core mathematical concept is the definition and geometric construction of a triangle, involving points, line segments, and closed polygons. Construction steps: create three free points A, B, C, then apply the Polygon command to connect them in order; GeoGebra automatically produces the triangle and its edges. This example is suitable for middle school geometry introduction, helping students understand the fundamental components of a triangle and the use of the polygon tool in GeoGebra, and serves as a foundation for more advanced triangle constructions such as medians or angle bisectors.