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#1 2013-09-29 06:45:25

jacks
Member
Registered: 2012-11-21
Posts: 80

Total no. of Triangle,Square and Rectangle

[1] Calculation of Total no. of Triangles form joining any 3  points in a Given Figure.

[2] Calculation of Total no. of Square form joining any 4 points in a Given Figure.

[2] Calculation of Total no. of Rectangle form joining any 4 points in a Given Figure.

View Image: triangle.jpg

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#2 2013-09-29 09:11:46

bob bundy
Moderator
Registered: 2010-06-20
Posts: 6,425

Re: Total no. of Triangle,Square and Rectangle

hi jacks,

I suggest you start with squares; that looks easiest to me.

You can have squares that are 1 by 1; 2 by 2; 3 by 3; and 4 by 4.

EDIT:  You should also count the squares that are at 45 degrees to the grid.

There's an easy pattern to this, so finding that is a good beginning to the harder rectangle case.

Bob

Last edited by bob bundy (2013-09-29 09:13:07)


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#3 2013-09-29 11:11:50

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 87,219

Re: Total no. of Triangle,Square and Rectangle

Hi;


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

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