Inscribed angles are formed by two chords that share a common endpoint. Move any of points A, B, D, or E along the circle. What do you notice about the two angles? What happens if you move D or E onto the green arc?
[b]Rule: Inscribed angles subtended by the same arc are congruent.[/b] [i]Translation:[/i] angles on a circle that are across from the same arc will have the same angle.