2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/120377In this paper, we state the validity of Cramer's rule in a tropical context and its correspondence with classical Cramer's rule. This correspondence will allow us to prove a constructive version of Pappus' theorem conjectured in the paper First Steps in Tropical Geometry, math.AG/030636612 pages, 3 figures. Revised version but unedited with respect to the published version in the IMRNAlgebraic Geometry14A25; 15A03; 16Y60; 51A30text