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Slope

Middle School

Definition

A measure of how steep a line is, calculated as the ratio of vertical change to horizontal change.

m = (y₂ - y₁)/(x₂ - x₁) = (Δ y)/(Δ x)

Slope of a line through two points

y = mx + b

Slope-intercept form of a line

m₁ · m₂ = -1

Condition for perpendicular lines

Example 1

Find the slope of the line through (1, 2) and (4, 8).

Example 2

What slope is perpendicular to a line with slope 3?

Velocity, acceleration graphs

Marginal cost, marginal revenue