 # 9.04 Transformation of shapes

Lesson

## Ideas

Do you remember what a  measure of turn  is?

### Exploration

Based on the circle above, a quarter turn indicates a 90\degree degrees, a half turn indicates a 180\degree degrees, and a full turn of circle indicates a 360\degree degrees.

### Examples

#### Example 1

A right angle is a:

A
Quarter turn
B
Half turn
Worked Solution
Create a strategy

Remember that 4 right angles make up a circle.

Apply the idea

Since 4 right angles make up a circle, and a circle makes up a full turn, a right angle is \dfrac{1}{4} of a circle or a quarter turn.

The answer is A: Quarter turn.

Idea summary

A right angle is a quarter turn around a circle.

## Slides

Let's look at slides first, where we change the position of a shape. Slides are also called translations.

### Examples

#### Example 2

Choose the picture that shows a translation.

A
B
C
Worked Solution
Create a strategy

Choose the option where both objects are facing the same way.

Apply the idea

Option B is the correct answer because the sock has been slid but has not flipped or turned.

Idea summary

A slide or translation is when the object moved along a straight line.

## Flips

Now let's look at flips in this video. Flips are also called reflections.

### Examples

#### Example 3

Choose the picture that shows a reflection.

A
B
C
Worked Solution
Create a strategy

Choose the option that shows two objects that are mirror-images of each other.

Apply the idea

Option C is the correct answer because the two kangaroos are mirror-images of each other.

Idea summary

A flip or reflection is when the object is flipped or reflected across a line, and the result is a mirror image.

## Turns

Now let's learn about turns, which change the orientation of a shape or object. Turns are also called rotations.

### Examples

#### Example 4

Choose the picture that shows a rotation.

A
B
C
Worked Solution
Create a strategy

Choose the option that shows two objects where one object is turned.

Apply the idea

Option C is the correct answer because the hammer on the right has been turned.

Idea summary

Translations, reflections and rotations change the position or orientation of the shape, but the shape itself stays the same.

### Outcomes

#### VCMMG200

Describe translations, reflections and rotations of two-dimensional shapes. Identify line and rotational symmetries