SOLUTION: what is the product of two consecutive integers is 1 more than their sum. Find the integers?

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Question 222965: what is the product of two consecutive integers is 1 more than their sum. Find the integers?
Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
Consecutive integers are 1 apart from each other. So if one integer is "x" then the next one is "x+1". Now let's use these to translate
"the product of two consecutive integers is 1 more than their sum"

Product means multiplication so "the product of two consecutive integers" is (x)(x+1). Sum means addition so "their sum" is (x) + (x+1)

So "the product of two consecutive integers is 1 more than their sum" translates into:
%28x%29%28x%2B1%29+=+1+%2B+%28x%29+%2B+%28x%2B1%29
Now we just need to solve this. Start by simplifying each side:
x%5E2+%2B+x+=+2x+%2B+2
Next, since this is a quadratic equation (because of the x%5E2), we will get one side equal to zero by subtracting the entire right side from both sides:
x%5E2+-+x+-+2+=+0
Now we can solve this by factoring (or by using the quadratic formula):
x+-+2%29%28x+%2B+1%29+=+0
The Zero Product Property tells us that if this or any product is equal to zero then one or more of the factors must be zero. So:
x-2+=+0 or x%2B1+=+0
Solving each of these simple equations we get:
x+=+2 or x+=+-1
Now remember what "x" represents. (Look back at the beginning.) It represents the first (or smaller) of the two consecutive integers. And (x+1) represents the second (or larger) of the two. We have found two values for x: 2 and -1. So we have found two pairs of consecutive integers:
  • 2 and 3
  • -1 amd 0

You can check them out and they both work:
  • 2*3 is one more than 2+3
  • -1*0 is one more than -1+0