MathDB
Turkish NMO First Round - 2012 Problem - 25 {Geometry}

Source:

July 1, 2012
geometrytrigonometrycircumcircle

Problem Statement

The midpoint MM of [AC][AC] of a triangle ABC\triangle ABC is between CC and the feet HH of the altitude from BB. If m(ABH^)=m(MBC^)m(\widehat{ABH}) = m(\widehat{MBC}), m(ACB^)=15m(\widehat{ACB}) = 15^{\circ}, and HM=23|HM|=2\sqrt{3}, then AC=?|AC|=?
<spanclass=latexbold>(A)</span> 6<spanclass=latexbold>(B)</span> 52<spanclass=latexbold>(C)</span> 8<spanclass=latexbold>(D)</span> 163<spanclass=latexbold>(E)</span> 10 <span class='latex-bold'>(A)</span>\ 6 \qquad <span class='latex-bold'>(B)</span>\ 5 \sqrt 2 \qquad <span class='latex-bold'>(C)</span>\ 8 \qquad <span class='latex-bold'>(D)</span>\ \frac{16}{\sqrt3} \qquad <span class='latex-bold'>(E)</span>\ 10