Bisect an Angle with Compass and Straightedge

This GeoGebra example demonstrates the classic compass-and-straightedge construction for bisecting an angle. The core mathematical concept is the angle bisector theorem, where every point on the bisector is equidistant from the two sides of the angle)Skip. The construction uses a ray tool to define the two sides of the angle, then a circle tool centered at the vertex to mark two intersection points on the sides. From those points, two equal-radius circles are drawn; their intersection gives a point on the bisector. Finally, a line tool connects the vertex to that intersection to produce the angle bisector. Key GeoGebra commands include Line, Intersect, Point, Circle, and Ray, with objects such as vertex A, rays f and g, auxiliary circles c and h, and intersection points X, Y, V, W. This is ideal for middle school geometry lessons or self-study, helping learners visualize the logical steps of classical geometric construction.