Types of Graphs

Line Graph

A line graph is used to show the relationship between the independent and dependent variables and to determine the direction of the relationship between variables, that is, whether they are directly or inversely related. This kind of graph is more commonly used to organize quantitative data because it is simpler to make.

When both variables are directly related, the line on the graph is in an upward direction to the right of the graph, indicating that when the value of the independent variable increases, then the value of the dependent variable also increases.

An example of directly related variables is between the volume of gas in a car tire and the temperature of the surroundings. The higher the temperature of the surroundings, the more the volume of the gas expands. This explains why, during hot days, tires of cars traveling on the road may explode. In this direct relationship, the temperature is the independent variable while the volume of the gas in the car tire is the dependent variable.