1993 OIM Problems/Problem 5

Revision as of 13:19, 13 December 2023 by Tomasdiaz (talk | contribs) (Created page with "== Problem == Let <math>P</math> and <math>Q</math> be two different points on the plane. Let us denote by <math>m(PQ)</math> the bisector of the segment <math>PQ</math>. Let...")
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

Problem

Let $P$ and $Q$ be two different points on the plane. Let us denote by $m(PQ)$ the bisector of the segment $PQ$. Let $S$ be a finite subset of the plane, with more than one element satisfying the following properties:

a. If $P$ and $Q$ are points distinct from $S$, then $m(PQ)$ intersects $S$.

b. If $P_1Q_1$, $P_2Q_2$and $P_3Q_3$are three different segments whose ends are points of $S$, then no point of $S$ belongs simultaneously to the three lines $m(P_1Q_1)$, $m(P_2Q_2)$. and $m(P_3Q_3)$.

Determine the number of points that $S$ can have.

~translated into English by Tomas Diaz. ~orders@tomasdiaz.com

Solution

This problem needs a solution. If you have a solution for it, please help us out by adding it.

See also

https://www.oma.org.ar/enunciados/ibe8.htm