Answer
$y\gt-\dfrac{1}{2}$
Work Step by Step
Remember, when we divide by a negative number, we flip the sign of the inequality. Using the properties of inequality, the solution to the given inequality, $
8-2y\gt9
,$ is
\begin{array}{l}\require{cancel}
-2y\gt9-8
\\\\
-2y\gt1
\\\\
y\lt\dfrac{1}{-2}
\\\\
y\lt-\dfrac{1}{2}
.\end{array}