SOLUTION: Find 3 odd consecutive intergers such that the product of the first and third minus the middle intergers is 338.

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Question 858210: Find 3 odd consecutive intergers such that the product of the first and third minus the middle intergers is 338.
Answer by ramkikk66(644) About Me  (Show Source):
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Find 3 odd consecutive integers such that the product of the first and third minus the middle integer is 338.
Ans:
Let the 3 odd integers be n-2,n and n+2
Product of 1st and 3rd = %28n+-+2%29%2A%28n+%2B+2%29+=+n%5E2+-+4
Subtracting middle integer
n%5E2+-+4+-+n+=+338
Or
n%5E2+-n+-+342+=+0
This is a simple quadratic equation which can be solved by factorizing.
n%5E2+%2B+18%2An+-+19%2An+-+342+=+0
%28n+%2B+18%29+%2A+%28n+-+19%29+=+0
So possible solutions for n are n+=+-18 or n+=+19

Correspondingly, the 3 numbers are (-20,-18,-16) or (17,19,21)

Since is is not mentioned that the integers are positive, both solutions are valid.

Check: %28-20%29%2A%28-16%29+-+%28-18%29+=+320+%2B+18+=+338
17%2A21+-+19+=+357+-+19+=+338
Both are correct!

:)