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#1 2007-04-10 09:00:11
- U7109
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Help Needed
Geometry has always been my best subject in maths... now I'm stuck on angles and shapes! Could someone tell me the name of a twenty-sided shape and how big 222 degrees is on a protractor?
: Falling asleep here..... I know you'e out there ..... please reply .....
"Reality leaves a lot to the imagination," ~ John Lennon
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#2 2007-04-10 09:39:39
- Devantè
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Re: Help Needed
An icosahedron is a twenty-sided regular geometric solid.
I don't know what you mean by your second question, could you please explain more?
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#3 2007-04-10 09:39:52
- JaneFairfax
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Re: Help Needed
A 20-sided polygon is called an icosagon. 
As for 222°, its a reflex angle. You might need a circular protractor to measure a reflex angle. Or you can meausre the other angle and subtract that from 360°.
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#4 2007-04-10 09:42:45
- Devantè
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Re: Help Needed
Yep. Plus, in GCSEs and exams, they'll most likely give you their own protractors, and not let you use your own. You'll almost certainly get the 180° protractor version (the one shaped like a semi-circle), so it's best to learn how to use that.
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#5 2007-04-10 23:30:06
- mathsyperson
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Re: Help Needed
I've never heard of that happening. They might provide protractors to people who forget theirs if they're nice, but I don't think they'd take yours away.
I've only known that to happen with calculators. Either way though, the 360 - angle technique is a good one to know. It opens up a few shortcuts.
Why did the vector cross the road?
It wanted to be normal.
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#6 2007-04-11 18:01:35
- U7109
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Re: Help Needed
Thanks. I'm going to high school here in Australia next year and I need to know this stuff.
Last edited by Choco (2007-04-11 18:01:53)
"Reality leaves a lot to the imagination," ~ John Lennon
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#7 2007-04-11 19:27:45
- Stanley_Marsh
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Re: Help Needed
Why English naming is so troublesome. In China , we name it by the number of sides (Literally translate it in English (four sided shape , five sided shape ......) , , if all sides are equal then + (zheng) , in front of the name.
Last edited by Stanley_Marsh (2007-04-11 19:28:27)
Numbers are the essence of the Universe
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#8 2007-04-13 10:15:05
- Devantè
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Re: Help Needed
Yea, language-differing terms drag.
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#9 2007-04-13 23:20:17
- mathsyperson
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Re: Help Needed
But practically all terms are different in different languages. If they weren't, we wouldn't have different languages in the first place.
Why did the vector cross the road?
It wanted to be normal.
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