Three Planes Intersecting at One Line

This example demonstrates the geometric phenomenon of three planes intersecting at a single line in 3D space. The core math concepts involved include solid geometry, vectors, and spatial line equations. The construction uses GeoGebra commands CurveCartesian to create the curves c, d, e, and object a for auxiliary purposes. Suitable for high school solid geometry teaching, spatial visualization training, and university introductory geometry courses.