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Guest Message by DevFuse
 

Photo
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4 points, 2 lengths


Best Answer plasmid, 04 March 2013 - 03:35 AM

Without any sort of formal proof, I think that these are all possible shapes. Although I haven't yet fully convinced myself that the last shape I drew actually exists. It seems like it should though.

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#11 plasmid

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Posted 08 March 2013 - 05:07 AM

Ah, I see... a pentagon minus one point. Which I guess would be the only answer if there were five points instead of four.
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#12 bonanova

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Posted 08 March 2013 - 05:42 AM

Ah, I see... a pentagon minus one point. Which I guess would be the only answer if there were five points instead of four.

 

Yes, I think it's the only five-point case.

 

When a friend asked me this question a few years ago, I was certain, after finding the first five, that I had them all.

Then he said, what if there were five points? :duh:

I believe he said the problem came from a Jr. High. math competition that he had organized.

We ate the rest of our lunch in silence.


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