Depending on the type of numbers you are considering, (ex: fractions, decimals, whole numbers) there can be multiple or even a limited amount of possibilities. If you are using whole number however this can be achieved by multiplying 1 x 99 = 99, or 3 x 33 = 99. Hope this helps :) Best of luck.
There are an infinite number of possibilities.
If you want to stick with only positive whole numbers,
then there are only three possibilities:
1 x 99
3 x 33
9 x 11
99
(33,3)(11,9)
1 x 891, 3 x 297, 9 x 99, 11 x 81, 27 x 33
11 and 9
1 x 198, 2 x 99, 3 x 66, 6 x 33, 9 x 22, 11 x 18
99
(33,3)(11,9)
33 x 3 = 99
1 x 891, 3 x 297, 9 x 99, 11 x 81, 27 x 33
-99 and 146
There are two combinations of numbers when multiplied together are equal to 15. 1 x 15 = 15 and 3 x 5 = 15.
97 and 2
11 and 9
1 x 198, 2 x 99, 3 x 66, 6 x 33, 9 x 22, 11 x 18
9x11
99
There are infinite numbers, but 11* 9 is fine.