Answer
slope=-$\frac{n}{2m}$
Work Step by Step
To find the slope of a line, we use the equation m=$\frac{y_{2}-y_{1}}{x_{2}-x_{1}}$. It's given that $x_{1}$=-m $x_{2}$=3m $y_{1}$=-n $y_{2}$=-n, so all we need to do is plug the givens into the slope equation.
m=$\frac{-n-n}{3m-(-m)}$=$\frac{-2n}{4m}$=-$\frac{n}{2m}$
