olymmath

AUSTRIAN-POLISH 1995 Problem 5

    ABCABC is an equilateral triangle. A1,B1,C1A_{1}, B_{1}, C_{1} are the midpoints of BC,CA,ABBC, CA, AB respectively. pp is an arbitrary line through A1A_{1} . qq and rr are lines parallel to pp through B1B_{1} and C1C_{1} respectively. pp meets the line B1C1B_{1}C_{1} at A2A_{2} . Similarly, qq meets C1A1C_{1}A_{1} at B2B_{2} , and rr meets A1B1A_{1}B_{1} at C2C_{2} . Show that the lines AA2,BB2,CC2AA_{2}, BB_{2}, CC_{2} meet at some point XX , and that XX lies on the circumcircle of ABCABC .

    Dataset text AI-MO AoPS. Quoted with source.

    Solutions

    No solution is on olymmath yet. Official and human solutions come first when they arrive. AI solutions come after them, with a label.

    Add a solution

    Similar problems

    These problems have the most words in common with this statement.

    Locator austrian-polish/1995/p5 · Tag 81XBAD54B4 · Edit this page on GitHub · Keys: j next, k previous