Integers

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Integers

by ketkoag » Sun Mar 29, 2009 6:09 am
If x and y are positive integers and 1 + x + y + xy = 15, what is the value of x + y?
A. 3
B. 5
C. 6
D. 8
E. 9

Please lemme know whether i've solved it correctly..
(x+1)(y+1) = 15
=> x=2, y=4.
=> C answer

OA: C
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Re: Integers

by Brent@GMATPrepNow » Sun Mar 29, 2009 6:17 am
ketkoag wrote:If x and y are positive integers and 1 + x + y + xy = 15, what is the value of x + y?
A. 3
B. 5
C. 6
D. 8
E. 9

Please lemme know whether i've solved it correctly..
(x+1)(y+1) = 15
=> x=2, y=4.
=> C answer

OA: C
Looks good to me!
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by kaf » Tue Mar 31, 2009 2:45 pm
Please how did you arrive at this

(x+1)(y+1) = 15
=> x=2, y=4.

thanks