# How to Describe a Reflection

## Describing a Reflection

A shape can be reflected. Every point on the shape is reflected in a line of reflection.

To describe a reflection, we need to say where the line of reflection is.

### The Line of Reflection

The line of reflection is a mirror line. It is the line a shape is reflected in.

The image below shows a shape reflected in a line of reflection.

## How to Describe a Reflection

Describing a reflection is easy.

### Question

Describe how the light blue shape below has been reflected to make the dark blue shape.

### Step-by-Step:

# 1

Find a point on the shape and the corresponding point on its reflection.

We will choose point **A** on the shape. Point **A'** is the corresponding point on the reflection.

# 2

Join the points with a line.

# 3

Mark the half way point of this line.

# 4

Find another point on the shape and the corresponding point on its reflection.

We will choose point **B** on the shape. Point **B'** is the corresponding point on the reflection.

# 5

Join the points with a line.

# 6

Mark the half way point of this line.

# 7

Join the half way points with a line.

We have found the line of reflection.

We can find the equation of the line.

# 8

Find the equation of the line.

The equation of the line is **y = x + 2**.

### Answer:

The shape has been reflected in the line **y = x + 2**: