What does a line graph primarily show?

A line graph primarily shows how a quantity changes over time or allows for the comparison of two related quantities. This is accomplished by plotting data points on a Cartesian plane where the x-axis typically represents time intervals or categories and the y-axis represents the values of the variable being measured. The points are connected by lines, which visually demonstrate trends, such as increases or decreases over the specified period.

For example, if you were to track the temperature over several days, the line graph would show the fluctuations in temperature at each point in time, making it easy to identify trends and patterns. This visual representation is particularly effective for indicating relationships, such as understanding how one variable affects another.