Mathematics for IGCSE & O level - Graphs In Practical Situations (Section 1 - No. 23)
How can you find the speed of an object moving along a distance-time graph?
By calculating the area under the graph.
By measuring the horizontal axis.
By calculating the gradient of the graph.
By measuring the vertical axis.
Explication
The speed is calculated by the gradient (rise/run) of the line.