Answer:
24t^2 + 11
Explanation:
There is a lot left out of this question. If you are allowed rational numbers, a common factor could be 24.
24(t^2 + 11/24) is one possibility.
I think what you mean is there an integer that is a common factor. There is not.
So the answer is 24t^2 + 11
There is one more thing that needs to be clarified. Can you give t a value? If you can, then t = 11
the common factor would be
11(24 * 11 + 1)
I doubt very much that this is what is meant, but the question really should make it clear.