5th Grade Math: Understanding Graphs

How to Understand Graphs

You're probably already familiar with bar and pie graphs, but there are lots of other types of graphs as well. Graphs can display information about two variables. For example, you could make a graph showing how much you've grown each year. In this case, 'growth' and 'time' are the two variables. Graphs usually have two axes: a horizontal (x) axis and a vertical (y) axis.

Coordinate Graphs

Coordinate graphs, or coordinate planes, are grids with two main axes (lines) labeled x and y. The points where any two lines intersect are labeled based on their distance from these two axes. For instance, two lines that intersect at (3, 5) would be three points above the x-axis and five points to the right of the y-axis. Here's another way to think about it: if you start at the center of the graph (the origin), you have to go 'over three, up five' to get to the point (3, 5).

Often, you'll work with coordinate graphs that just have the x and y axes labeled with general numbers (one, two, three and so on). Other times, the numbers on the axes will refer to something in real life, like the example we used earlier of your growth over time. For graphs like these, each point tells you something specific. For instance, a point at (12, 40) might mean that you were 40 inches tall when you turned 12 years old.

Line Graphs

Line graphs, also called line plots, work very much like coordinate graphs. However, they almost always give information about a real-world situation (such as how the two variables relate to each other). Just like with coordinate graphs, the points marked on line graphs show the value of one variable when the other variable has a certain value.

Let's return to the example of graphing your height throughout your life. If you made a line graph of this, you could label the x axis with each year, and then record your height for each year relative to the y axis. Since you probably grew more in some years than in others, this would most likely produce a line that generally slants upward from left to right.