You are here

Points in a Semicircle

Given a semicircle, extend its diameter an arbitrary distance to point P, draw PC at a convenient angle intersecting the circle at points B and C. At B and C erect perpendiculars to PC and extend them to cut the diameter at D and E. Prove that if O is the circle's center, DO=OE.

The Ladies' Diary, London, 1806

"Points in a Semicircle," Convergence (January 2005)