A Pyramid is a 3

Giza is the location of the Pyramid of Khufu (also known as the "Great Pyramid" and the "Pyramid of Cheops"); the somewhat smaller Pyramid of Khafre (or Kephren); the relatively modest-sized Pyramid of Menkaure (or Mykerinus), along with a number of smaller satellite edifices known as "Queen's pyramids"; and the Great Sphinx of Giza.

source:
en.wikipedia.org

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Pentagonal Pyramid has a Pentagon as its Base:

In geometry, a pentagonal pyramid is a pyramid with a pentagonal base upon which are erected five triangular faces that meet at a point (the vertex). Like any pyramid, it is self-dual. The regular pentagonal pyramid has a base that is a regular pentagon and lateral faces that are equilateral triangles.

source:
en.wikipedia.org

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classroom.synonym.com

Right Pyramid

Right Pyramid. A pyramid that has ... Oblique pyramid, regular pyramid, right regular pyramid, volume, surface area, tetrahedron, area of a regular polygon : this ...

source:
mathwords.com

Square Pyramid has a Square as its Base:

In geometry, a square pyramid is a pyramid having a square base. If the apex is perpendicularly above the center of the square, it is a right square pyramid, and has C 4v symmetry.

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en.wikipedia.org

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Triangular Pyramid has a Triangle as its Base:

The pyramids have square bases, are called square pyramids, a hexagonal pyramid has a base that is a hexagon and the pyramids have triangular bases called as triangular pyramids, and so on. Triangular pyramid have three triangles meet at a common point, called apex, which come off of a common triangular base..

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mathcaptain.com

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