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#1 2006-02-26 12:43:58
- razor
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Pentagram
we have a pentagram.How we can with two lines create nine not covertly triangles?
Last edited by razor (2006-02-26 12:47:57)
#2 2006-02-26 16:52:53
- MathsIsFun
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Re: Pentagram
I am not sure what "not covertly" means, but my biggest problem is: how is it possible to get nine triangles with only two lines? Best I can do is 5. I can get 9 with three lines!
"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman
#3 2006-03-02 02:49:49
- ashwil
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Re: Pentagram
Trick question!
A pentagram already has 5 triangles within it. Joining any two pairs of alternate nodes on the inner pentagon will create 3 new triangles within the central pentagon and one more with one of the extarnal points. Total 9.
#4 2006-03-02 02:53:24
- ashwil
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Re: Pentagram
Scrub that last post! That method actually creates 12 triangles!!
#5 2006-03-02 03:24:37
- krassi_holmz
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Re: Pentagram
Here's what I get:
Last edited by krassi_holmz (2006-03-02 03:25:35)
IPBLE: Increasing Performance By Lowering Expectations.
#6 2006-03-02 07:38:17
- MathsIsFun
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Re: Pentagram
Pentagram ... I should read more careully!
"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman
#7 2006-03-02 09:05:42
- mathsyperson
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Re: Pentagram
I agree with what krazzi has.
Why did the vector cross the road?
It wanted to be normal.
#8 2006-03-02 16:34:04
- krassi_holmz
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Re: Pentagram
Now the other main question: are there another combinations?
For which numbers it is possible to cut the pentagram(or we may start with circle) with k lines?
Hm... Interesting.
IPBLE: Increasing Performance By Lowering Expectations.