SOLUTION: The product of two consecutive positive even integers is 360. Find the integers. Thanks

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Question 48351: The product of two consecutive positive even integers is 360. Find the integers.

Thanks

Found 3 solutions by venugopalramana, stanbon, Nate:
Answer by venugopalramana(3286) About Me  (Show Source):
You can put this solution on YOUR website!
The product of two consecutive positive even integers is 360. Find the integers.
LET ANY EVEN INTEGER=2N...NEXT EVEN INTEGER =2N+2
2N(2N+2)=360
N(N+1)=90
N^2+N-90=0
(N+10)(N-9)=0
N=9
THE 2 EVEN INTEGERS ARE 2*9=18 AND 20

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
1st even number : 2x
2nd even number : 2x+2
EQUATION:
Product = 360
2x(2x+2)=360
x(x+1) = 90
x^2+x-90=0
(x+10)(x-9)= 0
x=-10 or x=9
But 2x must be positive,so
1st even number: 2x=18
2nd eve number : 2x+2 = 20
Cheers,
Stan H.

Answer by Nate(3500) About Me  (Show Source):
You can put this solution on YOUR website!
First Number: i
Second Number: i + 2
%28i%29%28i+%2B+2%29+=+360
i%5E2+%2B+2i+-+360+=+0
%28i+-+18%29%28i+%2B+20%29+=+0
i = 18 or i = -20 Remember: Positive
18 and 20
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ai%5E2%2Bbi%2Bc=0 (in our case 1i%5E2%2B2i%2B-360+=+0) has the following solutons:

i%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%282%29%5E2-4%2A1%2A-360=1444.

Discriminant d=1444 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-2%2B-sqrt%28+1444+%29%29%2F2%5Ca.

i%5B1%5D+=+%28-%282%29%2Bsqrt%28+1444+%29%29%2F2%5C1+=+18
i%5B2%5D+=+%28-%282%29-sqrt%28+1444+%29%29%2F2%5C1+=+-20

Quadratic expression 1i%5E2%2B2i%2B-360 can be factored:
1i%5E2%2B2i%2B-360+=+1%28i-18%29%2A%28i--20%29
Again, the answer is: 18, -20. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B2%2Ax%2B-360+%29