< PREVIOUS PROBLEM  |  NEXT PROBLEM >

In the figure below, the circles of centers O and A are tangent at B, the circles O and F are tangent at G. A chord CD of the circle O is tangent to the circle A at E and tangent to the circle F at H. BE and DG meet at a point P and BC and GH meet at Q. Prove that PQ and CD are parallel.

See also:
Typography of problem 56

I have used Geometry Expressions to visualize these geometric forms and check out a variety of conjectures. Geometry Expressions is the world's first Interactive Symbolic Geometry System. This means: Geometric figures can be defined by either symbolic constraints or numeric locations.