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MathNet 2010 — Part 05 Question 13

Math Olympiad Vault · MathNet 2010 — Part 05

Question 13

Let $ABC$ be a triangle and let $D, E, F$ be the midpoints of the sides $BC, CA, AB$. Prove that $\angle DAC = \angle ABE$ if and only if $\angle AFC = \angle BDA$.