Hi! My name is Karen and I'm in the 7th grade.

I need to know what kind of a polygon an undecagon is and how many sides it has. This is a problem in my math book.

Thank you for your help!


Hi Karen,

I looked for undecagon in my dictionary and found "a polygon having eleven sides". We have a list of the names of polygons with from 3 to 20 sides and on that list an eleven sided polygon is called a hendecagon. Both names come from the Greek word for an eleven sided polygon, . This word is constructed from two words "one" and "ten". The difference in the spelling of undecagon and hendecagon is a result of trying to put the sound of the Greek word into English.

Penny and Michael
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