[tex]\bf \begin{array}{lllll}
&x_1&y_1&x_2&y_2\\
% (a,b)
&({{ -3}}\quad ,&{{ 5}})\quad
% (c,d)
&({{ -3}}\quad ,&{{ -2}})
\end{array}
\\\\\\
% slope = m
slope = {{ m}}= \cfrac{rise}{run} \implies
\cfrac{{{ y_2}}-{{ y_1}}}{{{ x_2}}-{{ x_1}}}\implies \cfrac{-2-5}{-3-(-3)}\implies \cfrac{-2-5}{-3+3}
\\\\\\
\cfrac{-7}{0}\impliedby \textit{und}\textit{efined}[/tex]
so the slope is undefined.. meaning, is a "vertical line"
well, let's see hmm when y is 5, x is -3, when y is -2, x is still -3
let's graph that, check the picture below
