Åk 6–9
2.1 The Coordinate System Explained  
In chapter 2.4 covering negative numbers, we go through the number line and the placement of numbers on the number line.  When we have a number line, we usually place the numbers as points directly on the line.  We can take an example below where we have the numbers -3 and 4.

A coordinate system consists of two lines, one horizontal and one vertical. Both of these numbers lines are called axis.  Both axis meet where they have the value 0, and this point has been given the name the origin.

When you have a coordinate system, the axis create four different areas, and these are called quadrants; the 1st, 2nd, 3rd, and 4th quadrants.

A marked value on the numbers line is called a point, and is called this even in the coordinate system.  In a coordinate system, the position of a point is determined by using two values from the axis, an x-value and a y-value. These two values are the point’s coordinates.  Below, we have placed a point which has an x-value of  4 and a y-value of 2.  The point has the coordinates (4, 2).

In the next chapter, you will learn more about coordinates.