A distance-time graph's slope represents:

Concept: A distance-time graph, as the name implies, shows the distance traveled by an item in a given amount of time. 

The Y-axis in this graph represents distance, while the X-axis represents time. If the graph is a straight line, the object's motion is uniform. 

The slope of the straight-line graph remains constant regardless of the interval used. This means that an object's speed remains constant in uniform motion.

Speed is shown by the slope of the distance-time graph. Because the slope of a distance-time graph defines the speed of that body, the steeper the slope, the faster the body.