MathDB
interesting geometry problem

Source:

April 28, 2008
geometrygeometry proposed

Problem Statement

Let ABCD be a square and K be a circle with diameter AB. For an arbitrary point P on side CD, segments AP and BP meet K again at points M and N, respectively, and lines DM and CN meet at point Q. Prove that Q lies on the circle K and that AQ : QB = DP : PC.