MathDB
Points And Lines

Source: KöMaL A. 806

March 23, 2022
geometrykomalconfiguration

Problem Statement

Four distinct lines are given in the plane, which are not concurrent and no three of which are parallel. Prove that it is possible to find four points in the plane, A,B,C,A,B,C, and DD with the following properties:
[*]A,B,C,A,B,C, and DD are collinear in this order; [*]AB=BC=CDAB=BC=CD; [*]with an appropriate order of the four given lines, AA is on the first, BB is on the second, CC is on the third and DD is on the fourth line.
Proposed by Kada Williams, Cambridge