The subtle concavity of the pyramid's faces creates an illusion that can ... "In other words, the Great Pyramid is a concave octagonal pyramid, rather than the standard square pyramid," he added.

The Great Pyramid of Giza, thought to have four sides, may actually have eight. Researchers, including British Egyptologist Flinders Petrie, uncovered the mystery of its concave faces under ...

B) hexagonal pyramid. C) octagonal pyramid. What do you notice about the number of faces for each pyramid? The number of faces is 1 more than the number of sides of the base polygon.