SOLUTION: Can you explain how to to solve this problem? n=x ∑ = n^2-2n+1=630 n=12 Solve for x.

Algebra ->  Sequences-and-series -> SOLUTION: Can you explain how to to solve this problem? n=x ∑ = n^2-2n+1=630 n=12 Solve for x.       Log On


   

Question 1047682: Can you explain how to to solve this problem?
n=x
∑ = n^2-2n+1=630
n=12
Solve for x.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Can you explain how to to solve this problem?
n=x
∑ = n^2-2n+1=630
n=12
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If n = 12 , n^2-2n+1 = 144-24+1 = 121 = 11^2
If n = 13, n^2-2n+1 = 169-26+1 = 144 = 12^2
If n = 14, n^2-2n+1 = 196-28+1 = 169 = 13^2
If n = 15, 14^2 = 196
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Add those to get 690
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Ans: x = 15
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Cheers,
Stan H.
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