Functional Skills: Coordinates

Points can be plotted and lines can be drawn on a grids similar to that seen.

A grid is made by 2 lines crossing called axes, meeting at a point in the middle called the origin.

The x-axis is the horizontal axis (left to right) and the y-axis is the vertical axis (bottom to top).

Coordinates are described by a pair of coordinates (\textcolor{red}{x}, \, \textcolor{blue}{y}) and represented by a dot or cross. The x coordinate is always written first.

The origin has coordinates (0, 0).

Example: What are the coordinates of the point A on the grid?

For the x coordinate, go up from A to the x-axis. Read off the number:

\textcolor{red}{2}

For the y coordinate, go across from A to the y-axis. Read off the number:

\textcolor{blue}{-3}

So, the coordinates of A are:

(\textcolor{red}{2} , \, \textcolor{blue}{-3} )

Example: Plot the point (1, \, 3) on the grid.

Move right from the origin to find \textcolor{red}{1} on the x-axis.

Move up from 1 until you are level with \textcolor{blue}{3} on the y-axis.

Mark this position with a dot or a cross, and label it (\textcolor{red}{1}, \, \textcolor{blue}{3}).

You can connect points on a grid to make lines or 2D shapes.

e.g. the grid shows a triangle drawn by plotting 3 points and connecting them with straight lines.

We call the triangle ABC after the letters of its corners.

Note: You may be given dimensions in a question and have to use these to plot points and create 2D shapes.