Given :
Two equal chords AB and CD intersecting of point E.
Let O be the centre.
To Prove :
arc DA = arc CB
⇒ ∠AOD = ∠COB
Construction : Through O join OA, OB, OC and OD
Proof : We know that corresponding arcs of equal chords are equal.
We know that same arcs subtends equal angles at center.
[∵ We know that same arcs subtends equal angles at centre.]