Really need help

Hint: How many permutations of three numbers{-1, 0, 1} can you arrange so that their SUM is always zero?

3! = {-1, 0, 1} | {-1, 1, 0} | {0, -1, 1} | {0, 1, -1} | {1, -1, 0} | {1, 0, -1} (total: 6). But since you have unlimited supply of these tiles, then {0, 0, 0} would also qualify?? Makes sense?

I'm still gtting it wrong. Can i have another hint?

Im having something like this: there are 6 choices for the first two, and 2 for the rest, but this is incorrect

Oh, ok, ive got it now! Thanks for the hint!