Intersection of Chords in a Circle and Similar Triangles

This GeoGebra example demonstrates the intersecting chords theorem within a circle: when two chords intersect at an interior point, the products of the lengths of the resulting four segments are equal. The construction employs Circle to draw the circle, Point to define points on the circumference and the intersection, Segment to construct the chords and their four sub-segments, Intersect to locate the crossing point, and Angle to mark angles that establish similar triangles. Core mathematical concepts include circle geometry, chord intersection, similar triangles, proportional segments, and the algebraic equation relating the four segment lengths. It is suitable for middle school and high school geometry instruction, particularly for exploring the intersecting chords theorem and similarity-based proofs.