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Quadratic and Perfect Square Query II (Posted on 2016-05-21) Difficulty: 3 of 5
Determine all possible values of a positive integer N such that:
N2 + 72N is a perfect square.

No Solution Yet Submitted by K Sengupta    
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Possible solution Comment 1 of 1
72N should have the form 2aN+a^2, with 0<a<36. 

This lead to N=a^2/(72-2a)
With integers for N=3,9,24,49,75,128,289, 

And the squares are: 15,27,48,77,105,160,323.

  Posted by armando on 2016-05-21 10:15:17
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