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The product of two consecutive integers is 5 more than three time the larger. What are the integers?

User Rockin
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1 Answer

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When calculating consecutive integers, the smaller number is x and the larger number is (x + 1).
So the equation you can use is x + (x + 1) = 5 + 3(x + 1)
This is because the sum of the consecutive integers are equal to 5 more than 3 times the larger integer.
Now simplify:
x + (x + 1) = 5 + 3(x + 1)
2x + 1 = 5 + 3(x + 1)
2x + 1 = 5 + 3x + 3
2x + 1 = 3x + 8
Now isolate the variable:
2x + 1 = 3x + 8
Subtract 2x from both sides:
1 = x + 8
Subtract 8 from both side:
-7 = x
x = -7
So the smaller number is -7 and the larger number is -6.

Now check your answer:
-7 + (-7 + 1) = 5 + 3(-7 + 1)
-7 + (-6) = 5 + 3(-7 + 1)
-7 + (-6) = 5 + 3(-7 + 1)
-7 - 6 = 5 + 3(-7 + 1)
-13 = 5 + 3(-7 + 1)
-13 = 5 + 3(-6)
-13 = 5 + (-18)
-13 = 5 - 18
-13 = -13
This works!

So the integers are -7 and -6.
User Uday Kumar Das
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