SOLUTION: A pyramid has a triangle base and all edges in the pyrimaid are equal. If the volume is 90 what is the area of the base

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Question 1136805: A pyramid has a triangle base and all edges in the pyrimaid are equal. If the volume is 90 what is the area of the base
Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


The pyramid is a regular tetrahedron, with each face an equilateral triangle.

The formula for the volume of a regular tetrahedron with edge length s is

V+=+%28s%5E3%2Asqrt%282%29%29%2F12

The formula for the area of an equilateral triangle with side length s is

A+=+%28s%5E2%2Asqrt%283%29%29%2F4

Use the given volume in the volume formula to solve for the edge length s; then substitute into the area formula to find the area of the base.

Ugly with pencil and paper; use a calculator if a decimal approximation is acceptable.