What is the slope of $y=-1$ ?

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Answer 1 · 2016-05-13T23:35:38

$0$

The slope $m$ of a line passing through points $(x_1, y_1)$ and $(x_2, y_2)$ is the change in $y$ divided by the change in $x$ :

$m = (Delta y)/(Delta x) = (y_2-y_1)/(x_2-x_1)$

In our example, the line $y = -1$ passes through $(0, -1)$ and $(1, -1)$ , giving us a slope:

$m = (-1 - (-1))/(1 - 0) = 0/1 = 0$

The $y$ value does not change, while the $x$ value does.

What is the slope of y=-1 y=-1?