Identify each term in the polynomial: the terms are \$15q\( and \)-21p^{3}$.
Determine the degree of each term by finding the sum of the exponents of the variables in that term. For \$15q\(, the variable \)q$ has an exponent of 1, so the degree is 1.
For the term \(-21p^{3}\), the variable \(p\) has an exponent of 3, so the degree of this term is 3.
The degree of the polynomial is the highest degree among its terms. Compare the degrees of the terms: 1 and 3.
Conclude that the degree of the polynomial \(15q - 21p^{3}\) is the highest degree found, which is 3.