If x and y are positive integers and 11 + x + y + xy = 25, what is the value of x + y?  Pick one.
A) 3  B) 5  C) 6  D) 8  E) 9
Try each answer choices.   For A: 11 + 3 + xy = 25; xy = 11 (impossible, 11 prime number. 1 + 11 doesn't equal 3)   For B: 11 + 5 + xy = 25; xy = 9 (no combination of xy = 9 and x + y = 5)   For C: 11 + 6 + xy = 25; xy = 8 (x + y = 6; x = 2, y = 4 or x = 4, y = 2)   For D: 11 + 8 + xy = 25; xy = 6 (no combination of xy = 6 and x + y = 8)   For E: 11 + 9 + xy = 25; xy = 5 (impossible, 5 prime number. 1 + 5 doesn't equal 9)   Therefore, answer 6.
<result>C</result>
If x and y are positive integers and 11 + x + y + xy = 25, what is the value of x + y?