SOLUTION: If the sum of the first 2n terms of 2, 5, 8, .... is equal to the sum of the first n terms of 57, 59, 61...., then n is equal to-

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Question 965943: If the sum of the first 2n terms of 2, 5, 8, .... is equal to the sum of the first n terms of 57, 59, 61...., then n is equal to-
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
If the sum of the first 2n terms of 2, 5, 8, .... is equal to the sum of the first n terms of 57, 59, 61...., then n is equal to- 
%282n%2F2%29%282%2A2%5E%22%22%2B%282n-1%293%29%22%22=%22%22%28n%2F2%29%282%2A57%5E%22%22%2B%28n-1%292%29

n%284%5E%22%22%2B3%282n-1%29%29%22%22=%22%22%28n%2F2%29%28114%5E%22%22%2B2%28n-1%29%29

n%284%5E%22%22%2B6n-3%29%22%22=%22%22%28n%2F2%29%28114%5E%22%22%2B2n-2%29

n%281%5E%22%22%2B6n%29%22%22=%22%22%28n%2F2%29%28112%5E%22%22%2B2n%29

n%2B6n%5E2%29%22%22=%22%22%28n%2F2%292%2856%5E%22%22%2Bn%29

n%2B6n%5E2%29%22%22=%22%22%28n%2Fcross%282%29%29cross%282%29%2856%5E%22%22%2Bn%29

n%2B6n%5E2%29%22%22=%22%22n%2856%5E%22%22%2Bn%29

n%2B6n%5E2%29%22%22=%22%2256n%2Bn%5E2

5n%5E2-55n%29%22%22=%22%22%220%22

5n%28n-11%29%22%22=%22%22%220%22

5n=0;   n-11-0
n=0;    n=11

The desired answer is n=11 terms.

n=0 is a comical solution.  It's really a solution, too,
because if you take twice the sum of zero terms of the first
sequence you would have zero, and if you took the sum of zero 
terms of the second sequence you would also have zero.  And 
it's quite true that zero equals zero!  :)

Edwin