Answer
F(a+2) = (3a+11)/(a+2)
Explanation
F(x) = (3x + 5)/x
If you are to find F(a+2), you replace x with (a+2)
F(a+2) = (3(a+2)+5))/(a+2)
= (3a+6+5)/(a+2)
=(3a+11)/(a+2)