You can put this solution on YOUR website! If I understand the problem as you have written it:
(5x-3)/6 - (x+3)/6
since the denominators are already the same, we can rewrite the problem as such:
[(5x-3)-(x+3)]/6
now we can subtract like terms in the numerator:
(5x-x-3-3)/6 (I have rewritten the numerator)
(4x-6)/6
now to simplify:
2x-3/3 (your answer) as the terms have a common factor of 2.