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SMO 2006 Open Round 2 Question 1

SMO · SMO 2006 Open Round 2

Question 1

In triangle $ABC$, $\angle A=60^\circ$. Points $D,M$ lie on the line $AC$, and points $E,N$ lie on the line $AB$, such that $DN$ and $EM$ are the perpendicular bisectors of $AC$ and $AB$, respectively. Let $L$ be the midpoint of $MN$. Prove that $\angle EDL=\angle ELD$.