3
Part of 1996 Bundeswettbewerb Mathematik
Problems(2)
set of 4 lines such one is parallel to a medina determined by other 3
Source: 1996 German Federal - Bundeswettbewerb Mathematik - BWM - Round 1 p3
1/27/2020
Four lines are given in a plane so that any three of them determine a triangle. One of these lines is parallel to a median in the triangle determined by the other three lines. Prove that each of the other three lines also has this property.
combinatorial geometrygeometrymedian
Rectangles erected on sides of a triangle; a concurrence
Source: Bundeswettbewerb Mathematik (Germany) 1996, round 2, problem 3
12/31/2004
Let be a triangle, and erect three rectangles , , externally on its sides , , , respectively. Prove that the perpendicular bisectors of the segments , , are concurrent.
geometryrectanglecircumcirclegeometric transformationreflectionhomothetyvector