– Slope (m) is the ratio of rise to run between two points on the line: m = Δy/Δx.
– To find it on a graph: choose any two points on the line and compute (y2 − y1)/(x2 − x1).
– Special cases: vertical line → slope undefined; horizontal line → slope 0.
Example:
– If the line passes through (2, 3) and (5, 11), slope m = (11 − 3) / (5 − 2) = 8/3.