Problem
GEO-B2-M08-P001 Equal Inscribed Angles
#1
★★☆☆☆ Level 2 of 5
Prove that if \(\angle AXB=\angle AYB\), then points \(A,B,X,Y\) lie on one circle.
Both angles subtend segment \(AB\).
By the converse of the inscribed angle criterion, equal angles subtending the same segment \(AB\) imply that the vertices of these angles lie on one circle with \(A\) and \(B\). Hence \(A,B,X,Y\) are concyclic.
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