SOLUTION: Find two consecutive odd integers such that the square of the first, added to 3 times the second, is 24.

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Question 289: Find two consecutive odd integers such that the square of the first, added to 3 times the second, is 24.
Answer by arden42(16) About Me  (Show Source):
You can put this solution on YOUR website!
Lets call our integers i and j. Any 2 consecutive odd integers will always be 2 apart, so we can first say that:
j+=+i+%2B+2
From the remainder of the question, we can say that:
i%5E2+%2B+3j+=+24
Substituting the first equation in the second gives:
i%5E2+%2B+3%28i+%2B+2%29+=+24
Rearranging and expanding brackets gives us a quadratic equation:
i%5E2+%2B+3i+-+18+=+0
Factorising it gives:
%28i+-+3%29%28i+%2B+6%29+=+0
Therefore i is either 3 or -6. Since i is odd according to the original question, i must be 3.
Since j is the following odd integer after i, j must be 5.
Result:
The 2 integers are 3 and 5.