2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/100168We show that the number of non-trivial rational points of height at most $B$, that lie on the cubic surface $x_1x_2x_3=x_4(x_1+x_2+x_3)^2$, has order of magnitude $B(\log B)^6$. This agrees with the Manin conjecture.38 pages; corrected versionNumber TheoryAlgebraic Geometry11G35text