Transformations

Transformations describe how shapes move or change through translation, reflection, rotation and enlargement. They link closely to coordinates, similarity and graph transformations.

Overview

A transformation changes the position, size or orientation of a shape.

The original shape is called the object, and the new shape is called the image.

In GCSE Maths, you need to recognise and describe four main transformations: translation, reflection, rotation and enlargement.

You should be able to recognise each transformation from a diagram and describe it using correct mathematical language.

What you should understand after this topic

  • Recognise each transformation from a diagram or description
  • Describe transformations fully using correct exam language
  • Use coordinate rules for reflections and rotations
  • Find centres of rotation and enlargement
  • Avoid common GCSE transformation mistakes

Key Definitions

Transformation

A change to a shape’s position, size or orientation.

Object

The original shape before a transformation.

Image

The new shape after a transformation.

Translation

A movement of a shape without changing size or orientation.

Reflection

A flip of a shape in a mirror line.

Rotation

A turn of a shape around a fixed point.

Enlargement

A change in size using a scale factor.

Scale Factor

The number that determines how much a shape is enlarged or reduced.

Centre of Rotation

The point around which a shape rotates.

Centre of Enlargement

The point from which a shape is enlarged.

Key Rules

Translation

Describe using a vector.

Reflection

Describe using the mirror line.

Rotation

Give the angle, direction and centre.

Enlargement

Give the scale factor and centre.

Quick Recognition

Translation example

Same size + moved

Translation

Reflection example

Same size + flipped

Reflection

Rotation example

Same size + turned

Rotation

Enlargement example

Different size

Enlargement

Describe Fully Checklist

Translation

Give the vector only.

Reflection

Give the exact mirror line.

Rotation

Give the angle, direction and centre.

Enlargement

Give the scale factor and centre.

How to Solve

Step 1: Understand transformations

A transformation maps an object to an image. It can move, flip, turn or resize a shape.

Object = original shape.
Image = transformed shape.
Exam tip: Always describe the transformation fully.
Transformations overview showing translation, reflection, rotation and enlargement

Step 2: Know the four transformations

Translation

Moves a shape using a vector.

Reflection

Flips a shape in a mirror line.

Rotation

Turns a shape around a centre.

Enlargement

Changes size using a scale factor.

Step 3: Translation

Every point moves the same distance and direction.

Move across first, then up/down.
Write as a vector.
Answer format: \(\begin{pmatrix}x \\ y\end{pmatrix}\)

Step 4: Reflection

A reflection flips a shape across a mirror line.

Give the equation of the mirror line.
Points stay the same distance from the line.

Step 5: Rotation

A rotation turns a shape around a centre.

State angle (90°, 180°, 270°).
State direction (clockwise/anticlockwise).
State centre of rotation.

Step 6: Enlargement

An enlargement changes size from a centre.

State the scale factor.
State the centre.
Scale factor > 1 → bigger, < 1 → smaller

Step 7: Describe transformations fully

Translation

Vector

Reflection

Mirror line

Rotation

Angle, direction, centre

Enlargement

Scale factor, centre

Step 8: Exam method summary

See graph transformations for functions.
  1. Compare object and image.
  2. Identify the transformation.
  3. Find key detail (vector, line, centre, scale).
  4. Use correct mathematical language.
  5. Check another point.

Example Questions

Edexcel

Exam-style questions inspired by Edexcel GCSE Mathematics.

Edexcel
Shapes A and B on a coordinate grid.
🔍 Click to enlarge

Describe fully the single transformation that maps shape A onto shape B.

Edexcel
Shape A and Shape B on a coordinate grid.
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Shape A is reflected in the x-axis and then translated by the vector \( \begin{pmatrix} c \\ d \end{pmatrix} \).
Find the value of c and the value of d.

Edexcel
Reflect the shaded shape in the mirror line.
🔍 Click to enlarge

Reflect the shaded shape in the mirror line.

Edexcel
Two triangles on a coordinate grid where triangle B is an enlargement of triangle A.
🔍 Click to enlarge

Here are two triangles on a grid. Triangle B is an enlargement of triangle A.
Write down the scale factor of the enlargement.

AQA

Exam-style questions based on the AQA GCSE Mathematics specification, focusing on clear reasoning, accurate diagram interpretation, and precise mathematical communication.

AQA
Coordinate grid showing rectangles A and B.
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Work out the vector that translates shape A to shape B.

AQA
Coordinate grid showing rectangles A and B on opposite sides of the y-axis.
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Rectangle A can be mapped onto rectangle B by a single transformation.

A student claims that the transformation is a reflection in the y-axis.

Is the student correct?

Tick one box. Yes ☐     No ☐

Give a reason for your answer.

AQA
Coordinate grid showing triangles P and Q.
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Here are two triangles, P and Q.

A student makes the following statement:

The transformation that maps triangle \(P\) onto triangle \(Q\) is a reflection in the line \(x = -1\).

Make one criticism of the student's statement.

AQA
Coordinate grid showing triangle ABC.
🔍 Click to enlarge

Here is triangle ABC on a coordinate grid.

Describe a single transformation that maps the triangle so that:

\(B\) remains fixed,

\(A\) maps to \((1, 1)\),

\(C\) maps to \((1, -1)\).

OCR

Exam-style questions aligned with OCR GCSE Mathematics, emphasising logical reasoning, problem-solving skills, and precise use of mathematical terminology.

OCR
Coordinate grid showing triangles A and B.
🔍 Click to enlarge

Triangle A and triangle B are drawn on a coordinate grid.

(a) Complete the following transformations of triangle A.

\(\text{(i) Draw the image of triangle } A \text{ after a rotation of } 180^{\circ} \text{ about } (0,0).\)

\(\text{(ii) Draw the image of triangle } A \text{ after a translation by the vector } \begin{pmatrix} 2 \\ -7 \end{pmatrix}.\)

\(\text{(b) Describe fully the single transformation that maps triangle } A \text{ onto triangle } B.\)

OCR
Coordinate grid showing triangles A and B.
🔍 Click to enlarge

(a) Draw the image of triangle A after a reflection in the line \( y = -1 \).

(b) Describe fully the single transformation that maps triangle A onto triangle B.

OCR

Exam Checklist

Step 1

Check whether the shape stayed the same size.

Step 2

Ask: did it move, flip, turn or resize?

Step 3

Track one point first, then confirm with another.

Step 4

Give every detail needed for full marks.

Most common exam mistakes

Rotation

Missing the centre or forgetting clockwise / anticlockwise.

Reflection

Giving the wrong mirror line or measuring distance incorrectly.

Translation

Writing the vector in the wrong direction.

Enlargement

Forgetting the scale factor or using the wrong centre.

Common Mistakes

These are common mistakes students make when working with transformations in GCSE Maths.

Missing rotation direction

Incorrect

A student gives the angle but not the direction.

Correct

Always state both the angle and the direction (clockwise or anticlockwise) for rotations.

Not stating the centre of rotation

Incorrect

A student describes the rotation without a centre.

Correct

Every rotation must include the centre of rotation as coordinates.

Incomplete “describe fully” answers

Incorrect

A student gives only part of the required information.

Correct

Include all details: rotation (angle, direction, centre), reflection (mirror line), translation (vector), enlargement (scale factor and centre).

Incorrect translation vector

Incorrect

A student gives the wrong direction or order.

Correct

Write vectors as \(\begin{pmatrix} x \\ y \end{pmatrix}\), where x is horizontal and y is vertical movement.

Incorrect reflection measurement

Incorrect

A student measures diagonally instead of perpendicular to the mirror line.

Correct

Reflection distances must be measured at right angles to the mirror line.

Describing enlargement vaguely

Incorrect

A student says “bigger” or “smaller”.

Correct

Always give the exact scale factor (e.g. scale factor 2 or 0.5).

Wrong centre of enlargement

Incorrect

A student uses an incorrect centre point.

Correct

Draw lines from corresponding points to find the correct centre of enlargement.

Misunderstanding negative scale factors

Incorrect

A student places the image on the same side.

Correct

A negative scale factor places the image on the opposite side of the centre of enlargement.

Try It Yourself

Practise performing and describing geometric transformations.

Questions coming soon
Foundation

Foundation Practice

Recognise and apply translations, reflections, rotations and enlargements.

Question 1

Which transformation has been applied to shape A to get shape B?

A B

Games

Practise performing and describing geometric transformations.

Frequently Asked Questions

What are the 4 transformations?

Translation, reflection, rotation and enlargement.

What does 'describe fully' mean?

Include all key details such as direction, angle, centre or scale factor.

Which transformations keep size?

Translation, reflection and rotation.