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An icosahedron is a regular polyhedron that has 20
All the faces are
and are all
that is, all the same size. It is one of the five
If s is the length of any edge, then each face has an area of
Since there are 20 faces, when we multiply the above by 20 and simplify, we get the surface area of the whole object. As the formula:
If s is the length of any edge, then the volume enclosed by the icosahedron is given by the formula:
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