Angle between Two Planes (Pyramid Model)

This GeoGebra example demonstrates how to find the angle between two planes using a four-sided pyramid model. The core mathematical concept is the dihedral angle in solid geometry: the angle between two planes is measured by the angle between two lines perpendicular to their intersection line, drawn from a common point on that line. The construction uses the Pyramid command to create the pyramid, OrthogonalLine and Intersect to locate perpendiculars and intersection points, and Line, Segment, and Angle to construct and measure the plane angle. This resource is ideal for high school solid geometry lessons, helping students visualize and compute dihedral angles, and also useful for introductory college geometry review.