Date: 05/01/2001 at 18:07:01 From: Mrs. Beauchamp's class Subject: Pyramids How many corners does a pyramid have? We have found that the point is called a vertex, but is this considered a corner?
Date: 05/06/2001 at 14:01:17 From: Doctor Douglas Subject: Re: Pyramids Hi everyone, A square pyramid (one that has a square base) has five vertices. If the pyramid has a triangular base, then it is called a "tetrahedron" and has only four vertices. Mathematicians prefer the word "vertex" because it is more *precise* than the word "corner." For example, we often think that a room has four corners because we are referring to the four vertical edges rather than the eight vertices. If this were the definition of "corner" that we are supposed to use for the square pyramid, then it would have four corners (and five vertices). I hope this helps. Please write back if you'd like to discuss this some more, or if you have other questions. - Doctor Douglas, The Math Forum http://mathforum.org/dr.math/
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