Lesson

We may be able to find where we live on a map, but would we describe it to somebody else? What if they were on the other side of the world and had no idea where our town was? A number line helps with direction, but only left and right, or up and down. This is where a number plane can help us.

A number plane is like having a horizontal number line and a vertical number line! We can describe the position of any point or location using two values, called a pair of coordinates.

A number plane is made up of a horizontal and a vertical axis.

- The horizontal axis, called the$x$
`x`-axis, is like a number line you have seen previously that runs from left to right. - The vertical axis, called the $y$
`y`-axis, is a number line that runs up and down. - The two lines meet at the origin, which has coordinates $\left(0,0\right)$(0,0).

A pair of coordinates describes a point's position away from the origin.

When we plot a pair of coordinates, we draw them on a number plane. For example, to plot the point $\left(2,5\right)$(2,5), we would start at the origin, move $2$2 spaces to the right and $5$5 spaces up.

To name coordinates, we write the horizontal value, then the vertical value that a point is away from the origin. Watch this video to learn more about plotting and naming points on the number plane.

Remember!

We write the horizontal $x$`x`-coordinate, then the vertical $y$`y`-coordinate $\left(x,y\right)$(`x`,`y`).

Just like the alphabet, $x$`x` comes before $y$`y`.

Now you can have a play with this applet to practise plotting some points.

Plot the point $\left(6,0\right)$(6,0) onto the number plane.

- Loading Graph...

Plot the point $\left(6,3\right)$(6,3) onto the number plane.

- Loading Graph...

What are the coordinates of the plotted point?

Loading Graph...

$\left(\editable{},\editable{}\right)$(,)

Connect members of sequential patterns with their ordinal position and use tables, graphs, and diagrams to find relationships between successive elements of number and spatial patterns.

Use a co-ordinate system or the language of direction and distance to specify locations and describe paths.