Identify Reflections on Coordinate Grids

In this activity, we will learn how to reflect a shape over the x-axis or y-axis.

Look at the following triangles drawn on a coordinate grid.

Shape A has been reflected in the x-axis to land on shape B.

This has been done by moving each corner across the mirror line, the same distance beyond.

Look at the following L-shapes drawn on a coordinate grid.

Shape A has been reflected in the y-axis to land on shape B.

This has been done by moving each corner across the mirror line, the same distance beyond.

Let's try an example question. 

Example

Look at the triangles on this coordinate grid.

On which triangle does triangle D land when it is reflected in the y-axis?

Answer

Triangle D lands on triangle A when it is reflected in the y-axis.

NB Triangle D lands on triangle K when it is reflected in the x-axis.

Let's have a go at some questions now.