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MathNet 2013 Question 47

Math Olympiad Vault · MathNet 2013

Question 47

D lies on side [AC] of an equilateral triangle ABC. Let F be the orthogonal projection of D onto BC, K the orthogonal projection of F onto AB, and E the orthogonal projection of K onto CA. Let L be the midpoint of [BC], and P the intersection of lines KE and FD. Prove that BP passes through the midpoint of [AL].