Triangle on a Line with Missing Angle Measures

This interactive example shows how to find the missing angle measures when several angles related to a triangle are not given and must be inferred from geometric angle relationships. The main ideas include straight-line (linear pair) angle relationships, the triangle angle-sum principle, and (where applicable) angle relationships arising from positioning on a line and using consistent constructions to set up solvable constraints. Construction uses GeoGebra tools such as Segment and Point to create the base line and triangle vertices, Polygon to form the triangle region, and Angle to label multiple angles to be determined (e.g., α, β, γ, δ, ε). A transformation command like Translate is used to reposition elements so the angle relationships align with the intended configuration. The setup is suitable for middle to high school learners and for practice on geometry angle-chasing problems.