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MathNet 1985 — Part 01 Question 35

Math Olympiad Vault · MathNet 1985 — Part 01

Question 35

$ABC$ is an acute angled triangle. The midpoints of $BC$, $CA$ and $AB$ are $D$, $E$, $F$ respectively. Perpendiculars are drawn from $D$ to $AB$ and $CA$, from $E$ to $BC$ and $AB$, and from $F$ to $CA$ and $BC$. The perpendiculars form a hexagon. Show that its area is half the area of the triangle.