Don't worry too much about the 'box' it is just a notation for function.
Since 9 is odd, the function (9) = 3(9) = 27
Since 6 is even, the function (6) = 1/2 * 6 = 3
So the product of function (9) * function (3) = 3*27 = 81
So, what you know is that the function(x) = 81
There are two possible functions here and neither are dependent on the even or oddness of the answer (which is 81), they are dependent on the even or oddness of the x. So, just solve:
if X is odd, then function(x) = 3(x)
We know the function(x) = 81
81 = 3x
x = 27 This works, X is odd. But this might not be the only answer.
You can try to see if x is even
I x is even, then function(x) = x/2
We know the function(x) = 81 so
81 = x/2
x = 2*81, which = 162 so Function(162) also = 81
SO function(9) * function(6) = function(27)
AND function(9) * function(6) = function (162)
Which is why the wording of the question is not what does function(9) * function (6) = but Which of the following is equivalent to...
Only function(27) is a choice (function(162) is not).
Answer is D ( 27 in the box)
-Carrie