Final answer:
Line graphs on a two-dimensional plot allow analysis of the relationship between two variables, typically with time as the independent variable and distance as the dependent variable.
Step-by-step explanation:
On a two-dimensional graph, line graphs allow for the effects of additional variables to be displayed and analyzed. A line graph is constructed with two axes: the horizontal axis (x-axis) represents the independent variable, and the vertical axis (y-axis) represents the dependent variable. By plotting data on these axes, it's possible to visualize the relationship between these two variables.
For example, if we have data on the distance a train travels over time, we can plot time on the horizontal axis and distance on the vertical axis to see how the distance changes in response to time. The relationship is often summarized in an equation of the general form y = mx + b, where m is the slope of the line, representing how much y changes for a given change in x, and b is the y-intercept, representing the value of y when x equals zero.