1999 IMO Problems/Problem 1
Problem
Determine all finite sets of at least three points in the plane which satisfy the following condition:
For any two distinct points and
in
, the perpendicular bisector of the line segment
is an axis of symmetry of
.
Solution
Upon reading this problem and drawing some points, one quickly realizes that the set
Alternate solutions are always welcome. If you have a different, elegant solution to this problem, please add it to this page.