Date: 08/05/97 at 23:56:14 From: Robert Richards Subject: Lengths of a sixteen-sided circle I am trying to cut a window for my twin girls' playhouse and would like to make a sixteen-sided window to go in the second floor hallway. I have tried to lay it out on cardboard using about every increment I can calculate for the total but it still doesn't work out. Can you help me out so I can tell where I am going wrong?
Date: 08/12/97 at 13:22:10 From: Doctor Rob Subject: Re: Lengths of a sixteen-sided circle You want the length of the side of a regular 16-sided polygon, right? Draw a circle of diameter d. Pick a point on the circle to be the starting point. Mark off points around the circle at regular intervals, to be connected up to make your 16-gon. You want to know what the length of these sides will be. The answer is d*Sqrt[2 - Sqrt[2 + Sqrt]]/2. This is approximately 0.19509*d. The central angle that each side corresponds to is 22.5 degrees. -Doctor Rob, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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