Answer
$m=1$
Work Step by Step
Using $m=\dfrac{y_1-y_2}{x_1-x_2}$, the slope of the line determined by the given points, $(
-1,10
) \text{ and } (
-9,2
),$ is
\begin{array}{l}\require{cancel}
m=\dfrac{10-2}{-1-(-9)}
\\\\
m=\dfrac{10-2}{-1+9}
\\\\
m=\dfrac{8}{8}
\\\\
m=1
.\end{array}