Texas Instruments
Texas Instruments: Relationship of Angles to the Circle
For this activity, students recognize the relationship of angles to circles. They study the Inscribed Angle Theorem and its corollaries.
Geometry Help
Geometry Help: Arcs, Angles, and Sectors
Explains the basic concept of arcs, angles, and sectors with step-by-step instructions and methods for solving specific problems on your own relating to this topic.