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MathNet 2022-part-05 — 197 problems (EN–VI) Question 55

Math Olympiad Vault · MathNet 2022-part-05 — 197 problems (EN–VI)

Question 55

In triangle $ABC$, let $B'$ and $C'$ be the midpoints of sides $AC$ and $AB$, respectively, and let $H$ be the foot of the altitude from vertex $A$. Prove that the circumcircles of triangles $AB'C'$, $BC'H$ and $B'CH$ pass through a common point $I$, and that the line $HI$ bisects the segment $B'C'$.