Answer
$m=\dfrac{3}{5}$
Work Step by Step
Through $(4,5)$ and $(-1,2)$
The slope of a line is given by $m=\dfrac{y_{2}-y_{1}}{x_{2}-x_{1}}$, where $(x_{1},y_{1})$ and $(x_{2},y_{2})$ are points through which the line passes.
Substitute the points given into the formula and evaluate:
$m=\dfrac{2-5}{-1-4}=\dfrac{-3}{-5}=\dfrac{3}{5}$