Barisal Secondary 2013 / 9

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Labib
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Joined:Thu Dec 09, 2010 10:58 pm
Location:Dhaka, Bangladesh.
Barisal Secondary 2013 / 9

Unread post by Labib » Mon Jan 13, 2014 7:41 pm

From the $16$ lattice points of the $3*3$ grid, you have to choose $6$ so that at least three of them are either collinear or they form a right triangle. In how many ways can this be done?
Last edited by *Mahi* on Tue Jan 14, 2014 3:00 pm, edited 1 time in total.
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Ragib Farhat Hasan
Posts:62
Joined:Sun Mar 30, 2014 10:40 pm

Re: Barisal Secondary 2013 / 9

Unread post by Ragib Farhat Hasan » Sat Jan 17, 2015 4:07 pm

Show the solution Labib bhai.

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