What is the slope formula?

What is the slope formula?

• A. (y1 - y2) / (x2 - x1)
• B. (y2 - y1) * (x2 - x1)
• C. (y2 - y1) / (x2 - x1)
• D. (x2 - x1) / (y2 - y1)

Answer: (C)

Slope tells you how steep a line, measured as the rise per run. If you look at two points (x1, y1) and (x2, y2), the vertical change is y2 − y1 and the horizontal change is x2 − x1. The slope is that ratio: (y2 − y1) / (x2 − x1). This tells you how much y increases for each unit x increases. If x2 − x1 = 0, the line is vertical and the slope is undefined. So the correct form is the ratio of the change in y to the change in x: (y2 − y1) / (x2 − x1). Using the opposite order in the numerator would flip the sign, and changing to multiplication or to the reciprocal would not express slope.

Slope tells you how steep a line, measured as the rise per run. If you look at two points (x1, y1) and (x2, y2), the vertical change is y2 − y1 and the horizontal change is x2 − x1. The slope is that ratio: (y2 − y1) / (x2 − x1). This tells you how much y increases for each unit x increases. If x2 − x1 = 0, the line is vertical and the slope is undefined.

So the correct form is the ratio of the change in y to the change in x: (y2 − y1) / (x2 − x1). Using the opposite order in the numerator would flip the sign, and changing to multiplication or to the reciprocal would not express slope.