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MathNet 2005 — Part 03 Question 35

Math Olympiad Vault · MathNet 2005 — Part 03

Question 35

Let $ABCD$ be an isosceles trapezoid with $AB = AD = BC$, $AB \parallel DC$, $AB \gt DC$. Let $E$ be the point of intersection of the diagonals $AC$ and $BD$ and $N$ be the symmetric point of $B$ with respect to the line $AC$. Prove that quadrilateral $ANDE$ is cyclic.