# Axes and coordinates

## Axes

All graphs have an -axis and a -axis. Here is a diagram of a typical set of axes.

• The point is called the origin.
• The horizontal axis is the -axis.
• The vertical axis is the -axis.
The x-axis is horizontal, and the y-axis is vertical.

One way to remember which axis is which is 'x is a cross so the -axis is across'.

## Coordinates

Coordinates are written as two numbers, separated by a comma and contained within round brackets. For example, , and .

• The first number refers to the -coordinate.
• The second number refers to the -coordinate.
Coordinates are written alphabetically - so x comes before y (x, y). One way to remember is 'you go along the hallway before you go up the stairs'.