Triangle Congruence - SA (Side-Angle) Dynamic Demonstration

This GeoGebra example dynamically demonstrates the Side-Angle (SA, i.e., SAS) condition for triangle congruence, showing that when two sides and the included angle are fixed, the triangle is uniquely determined. The core mathematical concept is the triangle congruence theorem, emphasizing the sufficiency of the side-angle-side criterion. Construction details: Point creates vertices A and B, Segment constructs side a, Rotate generates the included angle α, Angle marks the angle, and Ray with Intersect determines point C, completing the triangle. Multiple angles (α, β, γ) and segments (b, c, d, e, f, g) are linked dynamically. Suitable for middle school geometry lessons, helping students grasp why certain side-angle combinations guarantee congruence, and serving as a template for interactive teaching materials.