Line graphs

A line graph is often used to show a trend over a number of days or hours. It is plotted as a series of points, which are then joined with straight lines. The ends of the line graph do not have to join to the axes.

Reading line graphs

This line graph shows the midday temperature over a period of {7} days:

Representing data - Line graph

You can tell at a glance that the temperature was at its highest on Monday and that it started to fall in the middle of the week before rising again at the end of the week.


a) What was the lowest temperature, and on what day did it occur?

b) On what day was the midday temperature 26^\circ{C}?

a) The lowest temperature was 19^\circ{C}, and it occurred on Thursday.

b) The midday temperature was 26^\circ{C} on Tuesday.