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Topic: area of an octagon?
Replies: 2   Last Post: Jan 21, 2005 1:02 AM

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 Guess who Posts: 134 Registered: 1/25/05
Re: area of an octagon?
Posted: Jan 21, 2005 1:02 AM

On Thu, 20 Jan 2005 21:57:13 GMT, Kyle <Kypointguard@aol.com> wrote:

>Whats the formula for finding the area of a octagon

Divide the figure into triangles [8] wit hapex at the center.

Assume you are given the radius [semi-diagonal]," r", and the length
of side, "s". The length of the altitude of each trianbgle will be
given by sqrt(r^2 - (s/2)^2).

Now, the area of each triangle [and thre are 8 of them] will be half
the base tiems the altitude[height.]

You take it from there.

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Date Subject Author
1/21/05 Guess who
1/21/05 Bob