Problem

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Tags: geometry



A circle $\omega$ passes through the two vertices $B$ and $C$ of a triangle $ABC.$ Furthermore, $\omega$ intersects segment $AC$ in $D\ne C$ and segment $AB$ in $E\ne B.$ On the ray from $B$ through $D$ lies a point $K$ such that $|BK| = |AC|,$ and on the ray from $C$ through $E$ lies a point $L$ such that $|CL| = |AB|.$ Show that the circumcentre $O$ of triangle $AKL$ lies on $\omega$.