5-CIR-Theorem #1 Inscribed Angles
Angle PCD is an inscribed angle in the circle. It intercepts arc CD. The measure of arc CD is in green. 1. Drag point P without moving C or D. How does the measure of angle CPD change? Arc CD? 2. Drag points C and D. How does the measure of P change? 3. Make an arc with a measure of 180°. What is the measure of angle CPD?