MathDB

1

Part of 2003 China Second Round Olympiad

Problems(1)

Equal Angles

Source: 2003 China Second Round Olympiad

8/30/2014
From point PP outside a circle draw two tangents to the circle touching at AA and BB. Draw a secant line intersecting the circle at points CC and DD, with CC between PP and DD. Choose point QQ on the chord CDCD such that ∠DAQ=∠PBC\angle DAQ=\angle PBC. Prove that ∠DBQ=∠PAC\angle DBQ=\angle PAC.
trigonometrygeometry unsolvedgeometry