You can put this solution on YOUR website! The possible rational roots of a polynomial are all the ratios, positive and negative, which can be formed using a factor of the constant term (the term without a variable) over a factor of the leading coefficient (the number in front of the highest power term.
Your constant term is -3 and its factors are 1 and 3. (Since we're going to include all positive and negative ratios, we do not need to worry about whether the factors of -3 are -1 and 3 or 1 and -3.)
Your leading coefficient is 1 (the is the highest power term and it has an invisible 1 in front of it) and 1 is the only factor of 1.
So the possible rational roots of your polynomial are:
1/1, -1/1, 3/1 and -3/1
which simplify to:
1, -1, 3, -3
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