How many variables can be changed at a time on a line graph

A line graph uses points connected by lines (also called trend lines) to show how a dependent variable and independent variable changed. An independent variable, true to its name, remains unaffected by other parameters, whereas the dependent variable depends on how the independent variable changes. For temporal visualizations, time is always the independent variable, which is plotted on the horizontal axis. Then the dependent variable is plotted on the vertical axis.

Explanation:

As a good rule of thumb, don’t represent more than four variables on a line graph. With that many variables, the axis scales can become difficult to understand.

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