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Omni-MATH / A circle passes through vertex B of the triangle ABC, intersects its sides ABand BC at points K and L, respectively, and touches the side AC at its midpoint M. The point N on the a…

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problem

A circle passes through vertex BB of the triangle ABCABC, intersects its sides AB AB and BCBC at points KK and LL, respectively, and touches the side AC AC at its midpoint MM. The point NN on the arc BLBL (which does not contain KK) is such that ∠LKN=∠ACB\angle LKN = \angle ACB. Find ∠BAC\angle BAC given that the triangle CKNCKN is equilateral.
Plain-text mathematical notation (without MathML)
A circle passes through vertex B of the triangle ABC, intersects its sides ABand BC at points K and L, respectively, and touches the side AC at its midpoint M. The point N on the arc BL (which does not contain K) is such that ∠LKN=∠ACB. Find ∠BAC given that the triangle CKN is equilateral.
Original LaTeX notation
A circle passes through vertex $B$ of the triangle $ABC$, intersects its sides $ AB $and $BC$ at points $K$ and $L$, respectively, and touches the side $ AC$ at its midpoint $M$. The point $N$ on the arc $BL$ (which does not contain $K$) is such that $\angle LKN = \angle ACB$. Find $\angle BAC $ given that the triangle $CKN$ is equilateral.

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