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#1 2016-06-30 14:52:48
- Mathegocart
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- Registered: 2012-04-29
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Silly dot triangle problem
How many different non-congruent isosceles triangles can be formed by connecting three of the dots in a 4 x 4 square array of dots like the one shown below?
Two triangles are congruent if they have the same traced outline, possibly up to rotating and flipping. This is equivalent to having the same set of 3 side lengths.
Last edited by Mathegocart (2016-06-30 23:14:37)
The integral of hope is reality.
May bobbym have a wonderful time in the pearly gates of heaven.
He will be sorely missed.
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#2 2016-06-30 17:57:03
- bobbym
- bumpkin
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Re: Silly dot triangle problem
Hi;
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#3 2016-06-30 18:45:07
- thickhead
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Re: Silly dot triangle problem
{1}Vasudhaiva Kutumakam.{The whole Universe is a family.}
(2)Yatra naaryasthu poojyanthe Ramanthe tatra Devataha
{Gods rejoice at those places where ladies are respected.}
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#4 2016-06-30 23:15:20
- Mathegocart
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Re: Silly dot triangle problem
Both answers seem to be wrong. I have tried 148 and 4 as answers too.
The integral of hope is reality.
May bobbym have a wonderful time in the pearly gates of heaven.
He will be sorely missed.
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#5 2016-07-01 00:27:17
- thickhead
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Re: Silly dot triangle problem
I found 2 more adding upto 8.
{1}Vasudhaiva Kutumakam.{The whole Universe is a family.}
(2)Yatra naaryasthu poojyanthe Ramanthe tatra Devataha
{Gods rejoice at those places where ladies are respected.}
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#6 2016-07-01 16:59:15
- thickhead
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- Registered: 2016-04-16
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Re: Silly dot triangle problem
dots
A B C D
E F G H
I J K L
M N O P
The triangles
ABE ACI ADM of side length 1,2,3 respectively.
AFC of side length sqrt(2)
AJC of side length sqrt(5) third side 2
ANC of side length sqrt(10) third side 2
AJG of side length sqrt(5) third side sqrt(2)
AOL of side length sqrt(13)
ANH of side length sqrt(10) third of side 2*sqrt(2)
total 9
{1}Vasudhaiva Kutumakam.{The whole Universe is a family.}
(2)Yatra naaryasthu poojyanthe Ramanthe tatra Devataha
{Gods rejoice at those places where ladies are respected.}
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