[tex]\bf \begin{array}{ccccccccc}
&&x_1&&y_1&&x_2&&y_2\\
% (a,b)
&&(~ -8 &,& -8~)
% (c,d)
&&(~ -7 &,& 9~)
\end{array}
\\\\\\
% slope = m
slope = m\implies
\cfrac{\stackrel{rise}{ y_2- y_1}}{\stackrel{run}{ x_2- x_1}}\implies \cfrac{9-(-8)}{-7-(-8)}\implies \cfrac{9+8}{-7+8}
\\\\\\
\cfrac{17}{1}\implies 17
\\\\\\
% point-slope intercept
\stackrel{\textit{point-slope form}}{y- y_2= m(x- x_2)}\implies y-9=17[x-(-7)]
\\\\\\
y-9=17(x+7)[/tex]
