Pentagon
A pentagon has 5 straight sides
Pentagon
A pentagon is a 5-sided polygon (a flat shape with straight sides).
| This is a pentagon: | ![]() |
| And this is also a pentagon: | ![]() |
So long as it has 5 straight sides, it is still a pentagon
Regular or Irregular
If all angles are equal and all sides are equal, then it is regular, otherwise it is irregular
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| Regular Pentagon | Irregular Pentagons |
Is it a Pentagon?
A pentagon has 5 straight lines. The shape must also be closed (all the lines connect up).
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| Pentagon (straight sides) |
Not a Pentagon (has a curve) |
Not a Pentagon (open, not closed) |
Make a Regular Pentagon
You can make a regular pentagon with a strip of paper!
Start with a long strip of paper, make sure it is the same width all along (if you want the pentagon to be regular):

Make a "pretzel" knot with the paper.

Carefully tighten the knot while keeping the paper flat.
..... 
Trim off (or fold back) any excess.

All sides are now of equal length, and all angles should be the same too.




