MathDB
Turkish NMO First Round - 1999 P-21 (Geometry)

Source:

July 3, 2012
geometrytrigonometrycircumcirclegeometric transformationreflectiontrapezoidangle bisector

Problem Statement

ABC ABC is a triangle with \angle BAC \equal{} 10{}^\circ, \angle ABC \equal{} 150{}^\circ. Let X X be a point on [AC] \left[AC\right] such that \left|AX\right| \equal{} \left|BC\right|. Find BXC \angle BXC.
<spanclass=latexbold>(A)</span> 15<spanclass=latexbold>(B)</span> 20<spanclass=latexbold>(C)</span> 25<spanclass=latexbold>(D)</span> 30<spanclass=latexbold>(E)</span> 35<span class='latex-bold'>(A)</span>\ 15^\circ \qquad<span class='latex-bold'>(B)</span>\ 20^\circ \qquad<span class='latex-bold'>(C)</span>\ 25^\circ \qquad<span class='latex-bold'>(D)</span>\ 30^\circ \qquad<span class='latex-bold'>(E)</span>\ 35^\circ