Answer
(refer to the step by step part for the explanation)
$\\\\$Both the numerator and the denominator have errors. The correct value of the slope is:
$\\\\m=\dfrac{-5}{3}$
Work Step by Step
The numerator should be $-10-(-5)$ while the denominator should be $-8-(-11)$.
$\\\\$Thus, the correct calculation is:
$\\\\m=\dfrac{-10-(-5)}{-8-(-11)}
\\\\m=\dfrac{-5}{3}$