[tex]\bf slope = {{ m}}= \cfrac{rise}{run} \implies
\cfrac{{{ f(x_2)}}-{{ f(x_1)}}}{{{ x_2}}-{{ x_1}}}\impliedby
\begin{array}{llll}
average\ rate\\
of\ change
\end{array}\\\\
-------------------------------\\\\
\begin{cases}
x_1=0\\
x_2=8
\end{cases}\implies \cfrac{f(8)-f(0)}{8-0}\implies \cfrac{14-(-10)}{8-0}\implies \cfrac{14+10}{8}\implies \cfrac{3^o}{1hr}[/tex]