[tex]\bf \begin{array}{lllll}
&x_1&y_1&x_2&y_2\\
% (a,b)
&({{ 19}}\quad ,&{{ -16}})\quad
% (c,d)
&({{ -7}}\quad ,&{{ -15}})
\end{array}
\\\\\\
% slope = m
slope = {{ m}}= \cfrac{rise}{run} \implies
\cfrac{{{ y_2}}-{{ y_1}}}{{{ x_2}}-{{ x_1}}}\implies \cfrac{-15-(-16)}{-7-19}\implies \cfrac{-15+16}{-7-19}
\\\\\\
\cfrac{1}{-26}\implies -\cfrac{1}{26}[/tex]
