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In geometry, the orthopole of a system consisting of a triangle ABC and a line ℓ in the same plane is a point determined as follows. Let be the feet of perpendiculars dropped on ℓ from respectively. Let be the feet of perpendiculars dropped from to the sides opposite (respectively) or to those sides' extensions. Then the three lines are concurrent. The point at which they concur is the orthopole.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).