Respuesta :

The slope is defined as ratio of change is y-coordinate to the corresponding change in x-coordiante. So formula for the slope is,

[tex]m=\frac{dy}{dx}[/tex]

Part 1:

If line is horizontal, then y-coordinate remain same for the changes is x-coordinate, means if x-coordinate change by certain number then y coordinate does not change or value of dy is 0.

So slope of horizontal line is,

[tex]\begin{gathered} m=\frac{0}{dx} \\ =0 \end{gathered}[/tex]

Thus slope of horizontal line is 0.

Part 2:

If line is vertical then x-coordinate remain same for the change is y -coordinates, means if y-coodinate change by certain number then change in x-cordinate is 0 or value of dx is 0.

So slope of vertical line is,

[tex]\begin{gathered} m=\frac{dy}{0} \\ =\text{undefined} \end{gathered}[/tex]

Thus slope of vertical line is undefined.