For any northeast path v, we define two bivariate polynomials associated with the v-associahedron: the F and the H-triangle. We prove combinatorially that we can obtain one from the other by an invertible transformation of variables. These polynomials generalize the classical F and H-triangles of F. Chapoton in type A. Our proof is completely new and has the advantage of providing a combinatorial explanation of the nature of the relation between the F and H-triangle.