You can
put this solution on YOUR website!Your possible rational roots must be fractions or whole numbers whose numerators are factors of 15 and whose denominator must be factors of 4:
First the factors of the numerator are: 1, 3, 5, and 15.
The factors of the denominator are: 1, 2, and 4.
All possible factors with denominator of 1:

,

,

,

All possible factors with denominator of 2:

,

,

,

All possible factors with denominator of 4:

,

,

,
Put these in one list, and you have all the possible zeros of this polynomial.
R^2 at SCC