2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/163221This paper shows how a recent reformulation of the basics of classical geometry and trigonometry reveals a three-fold symmetry between Euclidean and non-Euclidean (relativistic) planar geometries. We apply this chromogeometry to look at conics in a new light.14 pages, 16 figures (in colour)Metric GeometryAlgebraic GeometryPopular Physics51N25; 83A05text