[tex]\bf \begin{array}{lllll}
&x_1&y_1&x_2&y_2\\
% (a,b)
&({{ 4}}\quad ,&{{ 8}})\quad
% (c,d)
&({{ 2}}\quad ,&{{ -2}})
\end{array}
\\\quad \\\\
% slope = m
slope = {{ \boxed{m}}}= \cfrac{rise}{run} \implies
\cfrac{{{ y_2}}-{{ y_1}}}{{{ x_2}}-{{ x_1}}}\implies \cfrac{-2-8}{2-4}
\\ \quad \\\\
% point-slope intercept
y-{{ y_1}}={{ \boxed{m}}}(x-{{ x_1}})\qquad \textit{plug in the values}\\
\left. \qquad \right.\uparrow\\
\textit{point-slope form}[/tex]
