SOLUTION: Find three consecutive multiples of 5 such that the sum of the squares of the first two is 125 greater than the square of the third. This is what I did, but it's wrong. {{{(5

Algebra ->  Sequences-and-series -> SOLUTION: Find three consecutive multiples of 5 such that the sum of the squares of the first two is 125 greater than the square of the third. This is what I did, but it's wrong. {{{(5      Log On


   



Question 330195: Find three consecutive multiples of 5 such that the sum of the squares of the first two is 125 greater than the square of the third.
This is what I did, but it's wrong.
%285N%29%5E2+%2B+%285N%2B5%29%5E2+-+125+=+%285N%2B10%29%5E2
25N + 25N + 25 - 125 = 25N + 100
25N - 100 = 100
25N = 200
N = 8

Found 2 solutions by Alan3354, hanah:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Find three consecutive multiples of 5 such that the sum of the squares of the first two is 125 greater than the square of the third.
This is what I did, but it's wrong.
%285N%29%5E2+%2B+%285N%2B5%29%5E2+-+125+=+%285N%2B10%29%5E2
This is ok, but you didn't square any terms.
25n%5E2+%2B+25n%5E2+%2B+50n+%2B+25+-+125+=+25n%5E2+%2B+100n+%2B+100
50n%5E2+%2B+50n+-100+=+25n%5E2+%2B+100n+%2B+100
25n%5E2+-+50n+-+200+=+0
n%5E2+-+2n+-+8+=+0
(n-4)*(n+2) = 0
n = 4
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25N + 25N + 25 - 125 = 25N + 100
25N - 100 = 100
25N = 200
N = 8

Answer by hanah(4) About Me  (Show Source):