SOLUTION: One number is three less than another. Their sum is fifteen. Find the numbers

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Question 31500This question is from textbook Elementary Algebra
: One number is three less than another. Their sum is fifteen. Find the numbers
 This question is from textbook Elementary Algebra

Answer by mbarugel(146) About Me  (Show Source):
You can put this solution on YOUR website!
Hello!
Let's call X and Y to your numbers.
We know that one number is three less than another. This means that X+=+Y+-+3
We also know that their sum is 15, so X+%2B+Y+=+15
Since we know that X = Y - 3, we use this in the "sum" equation to get:
X+%2B+Y+=+%28Y+-+3%29+%2B+Y+=+15
2Y+-+3+=+15
2Y+=+18
Y+=+9
So one of the numbers is 9. Since they must add to 15, then the other number must be 6.

I hope this helps!
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