## The Lesson

The y-coordinate is the second number in the pair of numbers used to describe Cartesian coordinates. For example, in the Cartesian coordinates**(2, 4)**, the y-coordinate is

**4**(the number on the right):

## What Does the Y-Coordinate Mean?

The y-coordinate tells you how far**up**(or

**down**) the vertical y-axis a point is on a graph (measured from the origin). If a point has Cartesian coordinates

**(2, 4)**, the point would be

**4**units up the y-axis. The image below shows what we mean by a point being 4 units along the x-axis (measured from the origin):

**Note:**The y-axis is labelled with numbers (0, 1, 2, 3...) so you can measure how far up the point is.

## The Y-Coordinate Can Be Positive...

If you go**up**the y-axis (above the x-axis), it is labelled with positive numbers (0, 1, 2, 3...). The y-coordinate of any point

**above**the x-axis is

**positive**. Imagine a point had an y-coordinate of

**4**. It would be

**4**units

**above**the y-axis:

## ...Or the Y-Coordinate Can Be Negative

If you go**down**the y-axis (below the x-axis), it is labelled with negative numbers (0, −1, −2, −3...). The y-coordinate of any point

**below**the x-axis is

**negative**. Imagine a point had an y-coordinate of

**-4**. It would be

**4**units

**below**the x-axis:

## Which Axis Is Which?

The**x is a cross**- so the

**x-axis goes across**!

The y-axis must go up.