does a vertical line has an undefined slope.

Question

jdoe0001 · Answer

$\bf slope = {\color{green}{ m}}= \cfrac{rise}{run} \implies \cfrac{{\color{blue}{ y_2}}-{\color{blue}{ y_1}}}{{\color{red}{ x_2}}-{\color{red}{ x_1}}}$

|dw:1389308251361:dw|

let 's pick 2 points there, say   (5, 4) and ( 5, 2)
let's find the slope

$\bf \begin{array}{lllll}
&x_1&y_1&x_2&y_2\
&({\color{red}{ 5}}\quad ,&{\color{blue}{ 4}})\quad &({\color{red}{ 5}}\quad ,&{\color{blue}{ 2}})
\end{array}
\\quad \

slope = {\color{green}{ m}}= \cfrac{rise}{run} \implies \cfrac{{\color{blue}{ y_2}}-{\color{blue}{ y_1}}}{{\color{red}{ x_2}}-{\color{red}{ x_1}}}$

what do you think?