Difference between revisions of "Mock AIME 4 2006-2007 Problems/Problem 6"

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For how many positive integers <math>n < 1000</math> does there exist a regular <math>n</math>-sided polygon such that the number of diagonals is a nonzero perfect square?
 
For how many positive integers <math>n < 1000</math> does there exist a regular <math>n</math>-sided polygon such that the number of diagonals is a nonzero perfect square?
 
==Solution==
 
==Solution==
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The formula for the number of diagonals of a convex n-gon is
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<math>\dfrac{n(n-3)}{2}</math>
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We need to find the number of n such that that is a perfect square.
  
 
{{solution}}
 
{{solution}}
 
  
  

Revision as of 11:40, 8 October 2007

Problem

For how many positive integers $n < 1000$ does there exist a regular $n$-sided polygon such that the number of diagonals is a nonzero perfect square?

Solution

The formula for the number of diagonals of a convex n-gon is

$\dfrac{n(n-3)}{2}$

We need to find the number of n such that that is a perfect square.

This problem needs a solution. If you have a solution for it, please help us out by adding it.