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Guest Message by DevFuse

# Circles to make a pentagon

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Posted 25 February 2014 - 05:35 PM

Using only a compass to make circles of any size you choose, find a method to locate five points that if connected would make a regular pentagon.

Is it possible to make a heptagon using a compass and circles?

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### #2 bonanova

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Posted 25 February 2014 - 09:19 PM

You'll need a straight edge (ruler) also.

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Vidi vici veni.

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Posted 26 February 2014 - 12:37 AM

Why would you need a straight edge? I just want points.
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### #4 bonanova

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Posted 26 February 2014 - 11:39 AM

Why would you need a straight edge? I just want points.

Spoiler for Because

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Posted 26 February 2014 - 05:01 PM

Why would you need a straight edge? I just want points.

Spoiler for Because

But remember, I do not need a line.  I just want the vertices that make the desired shapes.  There is no request to actually connect the vertices.

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### #6 bonanova

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Posted 27 February 2014 - 10:22 AM

Why would you need a straight edge? I just want points.

Spoiler for Because

But remember, I do not need a line.  I just want the vertices that make the desired shapes.  There is no request to actually connect the vertices.

Spoiler for I may be wrong but

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Posted 27 February 2014 - 12:29 PM

In the sense of needing to bisect a line....yes.
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### #8 TimeSpaceLightForce

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Posted 27 February 2014 - 05:40 PM

Spoiler for trying it with cad

Edited by TimeSpaceLightForce, 27 February 2014 - 05:44 PM.

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Posted 27 February 2014 - 09:09 PM

Spoiler for trying it with cad

well done.  Now about that heptagon.

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### #10 TimeSpaceLightForce

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Posted 28 February 2014 - 03:04 PM

Spoiler for

@BMAD my pentagon solution seems inaccurate.I found out the side length point at (+) being off . I would like to request your better solution for im having trouble with finding the last point of side length.

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