2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/195161In this work we present some classes of models whose the corresponding two coupled first-order nonlinear equations can be put into a linear form, and consequently be solved completely. In these cases the so-called trial orbit method is completely unnecessary. We recall that some physically important models as, for instance, the problem of tiling a plane with a network of defects and polymer properties are in this class of models.14 pages, 3 figuresHigh Energy Physics - Theorytext