Question 563239
This is the problem: 
Can you show that no polygon exists in which the ratio of the number of diagonals of the sum of the measures of its interior angles is 1:18? 
Here is my formula: 
n(n-3)/180(n-2)=1/18 
I don't know if the n(n-3) part is the formula for finding the number of diagonals. What is the the correct formula and what steps should I take in solving this problem?
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If the number of sides is n, the number of diagonals
= nC2 -n = (n(n-1))/2 - n = [n(n-1)-2n]/2 = [n^2-3n]/2 = [n(n-3)]/2
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Cheers,
Stan H.
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