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Guest Message by DevFuse

# Congruent polygons

4 replies to this topic

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Posted 24 February 2013 - 03:37 AM

Given that triangles have three sides and three angles we could share this information to another person to sketch our triangle.  Of course, it is a known fact that we only would need to share three parts (sides/angles) at a minimum with someone else in order for them to construct our shape (e.g. Side, Side, and Side; Side, angle, and side).  It is also known that to have someone build a quadrilateral for us, it would require five pieces of information.  But what about a pentagon, hexagon,..., octagon, ... n-agon?  Is there a generalizable formula as to the minimum amount of information needed for someone to construct your polygon unseen?

Shape:        Minimum Information Needed:

Triangle                     3

Pentagon

Hexagon

.....

Octagon

n-agon

• 0

### #2 Prime

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Posted 24 February 2013 - 06:13 AM

You need at least one side length among your three pieces of information for a triangle. Three angles won't do.

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Past prime, actually.

### #3 bonanova

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Posted 24 February 2013 - 07:57 AM   Best Answer

Spoiler for Pentagon

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Vidi vici veni.

### #4 googon97

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Posted 24 February 2013 - 04:39 PM

Spoiler for Agree with bonanova

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### #5 Prime

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Posted 24 February 2013 - 09:07 PM

Spoiler for Generalizable formula

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Past prime, actually.

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