SOLUTION: how many consecutive integers beginning with 1 would you have to add in order to get 2080? tnx.

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Question 720124: how many consecutive integers beginning with 1 would you have to add in order to get 2080? tnx.
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
Sn = n/2(2a+(n-1)d)
a=1,d=1 Sn=2080
2080= n/2[2+(n-1)1]
4160 = n(2+n-1)
4160= n^2+n
n^2+n-4160=0
n^2+65n-64n=4160=0
n(n+65)-64(n+65)=0
(n+65)(n-64)=0
n= 64