MathDB
Quadrilateral Practice!

Source: 2024 imocsl G2 (independent quiz P2)

August 8, 2024
geometryIMOC

Problem Statement

Triangle ABCABC has circumcenter OO. DD is an arbitrary point on BCBC, and ADAD intersects ⊙(ABC)\odot(ABC) at EE. SS is a point on ⊙(ABC)\odot(ABC) such that D,O,E,SD, O, E, S are colinear. ASAS intersects BCBC at PP. QQ is a point on BCBC such that D,O,A,QD, O, A, Q are concylic. Prove that ⊙(ABC)\odot(ABC) is tangent to ⊙(APQ)\odot (APQ).
Proposed by chengbilly
Back to ProblemsView on AoPS