Incribing a Pentagon in a Circle
Date: 2/6/96 at 16:43:28 From: Anonymous Subject: Inscribing a pentagon in a circle I'm stuck trying to inscribe a pentagon. I can easily inscribe a square by just drawing to perpendicular diagonals. I also know that 360/5 = 72 but that doesn't help me at all. Can you help? Thanks a googol. Evan.
Date: 3/10/96 at 0:18:54 From: Doctor Jodi Subject: Re: Inscribing a pentagon in a circle Wow Evan, I can't believe that you're thanking us a googol! (I just found out what that is, actually.... !) First of all, to inscribe any old pentagon in a circle, just drawing it should be easy enough. But if you want to draw a REGULAR pentagon, then it helps to know that each angle needs 72 degrees. Now you need to find a protractor and draw a line at 72 degrees from any one point on the circle to another. Now do the same thing starting with one of those two endpoints, etc., and continue until you get a regular pentagon. Let me know if this works. (On the other hand, you could draw a regular pentagon using a protractor and then draw a circle touching each of its 5 endpoints. But that would be too easy - don't you think?) -Doctor Jodi, The Math Forum
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