Answer: The only one of these that's an integer is 9.
Explanation: Let X be the integer. Then
X - 3/X = 26/3. Multiplying by 3X on both sides:
3X^2 - 9 = 26X
3X^2 - 26X - 9 = 0
X = (26 +/- SQRT(26^2-(4*(-27))))/6 = (26 +/- 28) / 6,
so the two solutions for X are 1/3 and 54/6 = 9.