Adding Complex Numbers and the Parallelogram Rule

① This example demonstrates the addition of two complex numbers on the complex plane and shows the parallelogram formed by the two addends and the origin. ② Core mathematical concepts include the geometric representation of complex numbers, vector addition, the parallelogram law, and translation transformations. ③ Construction highlights: GeoGebra commands Intersect, Segment, Distance, and Polygon are used to create objects z_1, z_2, z_3, a, b, c, d, poly1, representing the two addends, their sum, the vector segments, and the parallelogram region. ④ Suitable for high‑school mathematics (complex numbers elective) or introductory university courses, ideal for classroom demonstration, self‑study exploration, or inclusion in a teaching resource library.