2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/140591We prove that both classical Chevalley-Warning-Ax and Tsen theorems hold for the blowing up of a quintic 3-fold along a line of multiplicity 3. Both proofs, which are of the same spirit than the original ones, involve the description of this blowing-up as a subvariety of a toric variety.13 pages, no figureNumber TheoryAlgebraic Geometry11G25; 11T55;14G15; 14J30text