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
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