SOLUTION: The product of two consecutive even intergers is 360. Find the intergers.

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Question 113493: The product of two consecutive even intergers is 360. Find the intergers.
Found 2 solutions by Adam, MathLover1:
Answer by Adam(64) About Me  (Show Source):
You can put this solution on YOUR website!
I suppose that by sonsecutive you mean consecutive in terms of even nubers.Then we are looking for two numbers 2n and 2n+2 whoose product should be 360. Thus we have 2n*(2n+2) = 360.We could solve for n now, but we are not interested in n we need to know, what 2n equals. So we'll make substitution 2n = x, concluding with x*(x+2)=360. This can be easily solved for x, which yields two solutions 18 and -20. By adding +2 we have second numbers 20 and -18.
That means there are two pairs of numbers possible =>
18 : 20
-18 : -20
Adam

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

The product of two consecutive+even intergers is 360.
let first one be x, and second one be x%2B2
given:
x%28x%2B2%29+=+360
x%5E2+%2B+2x+=+360
x%5E2+%2B+2x+-+360+=+0.....use square root formula
x%5B1%2C2%5D=%28-b+%2B-+sqrt+%28b%5E2+-4%2Aa%2Ac+%29%29+%2F+%282%2Aa%29
x%5B1%2C2%5D=%28-2+%2B-+sqrt+%282%5E2+-4%2A1%2A%28-360%29+%29%29+%2F+%282%2A1%29

x%5B1%2C2%5D=%28-2+%2B-+sqrt+%284+%2B+1440+%29%29%2F2
x%5B1%2C2%5D=%28-2+%2B-+sqrt+%281444+%29%29%2F2
x%5B1%2C2%5D=%28-2+%2B-+38%29%2F2
x%5B1%5D=%28-2+%2B+38%29%2F2
x%5B1%5D=+36%2F2
x%5B1%5D=+18............one slution
x%5B2%5D=%28-2+-+38%29%2F2
x%5B2%5D=+-40%2F2
x%5B2%5D=+-20..........the other slution

check both solutions:
if x+=+18, then second integer will be 18+%2B+2 which is 20
let's check their product:

x%28x%2B2%29+=+360
18%2A20+=+360
360=+360...........


if x+=+-20, then second integer will be -20+%2B+2 which is -18
let's check their product:

-20%28-18%29+=+360
360+=+360............in both cases we have correct answer
so, your integers are:
1. 18and 20
2. -20 and -18