Cartesian planes Explained

Think about how you did dot-to-dot pictures as a young child. They relied on your counting ability and the pattern could only be created on the page they were printed on. Think about this as you view the following slides.

Suppose you were told to locate "(5, 2)" (pronounced as "the point five two" or just "five two") on the plane. Where would you look? To understand the meaning of "(5, 2)", you have to know the following rule: The x- coordinate (the number for the x- axis) always comes first. The first number (the first coordinate) is always on the horizontal axis.

Plot (5,2) Finding the location of (5,2) and then drawing the dot is called plotting (5,2)

Plot point (4,-5) When plotting remember the first number is for the horizontal (X) axis and the second for the vertical axis (Y).

Plot (-3,-1) As you can see a negative y- coordinate means you will be counting down the Y axis

Plot (-1,-3)

Pause the slide In your teams discuss why the coordinate version of this activity is more powerful.

Some Reasons The power of the coordinate approach is that from the list of coordinates alone, the graph can be transferred to any setting - another student, a computer program, or even the wall - where a coordinate plane is established. The coordinate version of this activity is also more explicit in nature, in that each point is plotted with respect to the origin rather than to the point preceding it.

Reference The purplemaths forums, retrieved from Illumination, Resources for teaching Math, retrieved from