Answer
not a monomial
Work Step by Step
RECALL:
(1) A monomial is a product of a constant and some variable/s whose exponents are nonnegative integers.
(2) The degree of a monomial is the sum of the exponents of its variables.
Using the rule $\dfrac{1}{y} = y^{-1}$, the given expression is equivalent to:
$=8x \cdot \frac{1}{y}
\\=8x \cdot y^{-1}
\\=8xy^{-1}$
The exponent of $y$ is $-1$, which is not a nonnegative integer.
Thus, the given expression is NOT a monomial.