Three oblique pyramids have the same regular square base. Which one has a volume of 15 cubic units if the area of the bases are all 15 square units? An oblique triangular pyramid is shown. The slant height is 5, the vertical height is 4, and the base of the triangle formed is 3. An oblique triangular pyramid is shown. The slant height is 5, the vertical height is 3, and the base of the triangle formed is 4. An oblique triangular pyramid is shown. The slant height is 15, the vertical height is 12, and the base of the triangle formed is 9.