What if x1 equals x2?

Then the line is vertical and the slope is undefined (infinite). We show a message in that case.

What does slope mean?

Slope is rise over run: how much y changes per unit change in x.

Slope between two points (x1,y1) and (x2,y2). Slope = (y2 - y1) / (x2 - x1).

What if x1 equals x2?: Then the line is vertical and the slope is undefined (infinite). We show a message in that case.
What does slope mean?: Slope is rise over run: how much y changes per unit change in x.

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