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# Congruent polygons

### #1

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

quadrilateral 5

Pentagon

Hexagon

.....

Octagon

n-agon

### #2

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.

Past prime, actually.

### #3

Posted 24 February 2013 - 07:57 AM Best Answer

*Vidi vici veni.*

### #4

Posted 24 February 2013 - 04:39 PM

### #5

Posted 24 February 2013 - 09:07 PM

Past prime, actually.

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