Answer
-1; 9
Work Step by Step
A term is composed of a numerical coefficient and a variable. The numerical coefficient is the constant in front of the variable of a term. The degree of a term is the power to which the variable of the term is raised.
Therefore, the numerical coefficient of the term $-y^{9}$, which can be rewritten as $-1\times y^{9}$, is -1.
The degree of $-y^{9}$ is 9, because the variable $y$ is raised to a power of 9.