Slides, Flips and Turns
Describe and perform translations, reflections and rotations of shapes; recognise what changes and what remains the same, and identify any symmetries.
Read this first
A shape can move without changing size. Only its position changes.
The shape slid across. It is the same size and shape.
Words you need
- Translation
- A slide. The shape moves without turning.
- Reflection
- A flip. The shape faces the other way.
- Rotation
- A turn around a point.
Worked example
e.g. A triangle is flipped over a line. What changes?
- Look at the size. It stays the same.
- Look at the shape. It stays the same.
- Look at which way it faces. That has swapped.
- Only the direction changed. Size and shape stayed.
After a slide, flip or turn, the shape is always the same size.
Practice
The pictures fade as you go. By the last few you are on your own.
1Which move is a slide?with a picture
AnswerA translation. It moved without turning.
2Which move makes a mirror image?with a picture
AnswerA reflection.
3You turn a square a quarter turn. Does it look different?with a hint
Need a hint?
Think about its lines of symmetry.
AnswerNo. A square looks the same.
4Does a reflection change the size?with a hint
Need a hint?
Compare the two shapes.
AnswerNo. Only the direction.
5Name the move: a shape is pushed 3 squares right.on your own
AnswerA translation.
6How many lines of symmetry has an equilateral triangle?on your own
AnswerThree.
7Which move would map a left hand onto a right hand?on your own
AnswerA reflection.
Think about it
1
What stays the same in every one of these moves?
One good answerThe size and the shape.
2
When does a turn make no visible change?
One good answerWhen the shape has rotational symmetry.
Common mistakes
Thinking a flip makes a shape bigger.
Size never changes. Only position or direction.
Mixing up a flip and a turn.
A flip makes a mirror image. A turn does not.