There are exactly four types of transformation at GCSE. When describing a transformation, you must give all the required details — missing one piece of information means lost marks.
1. TRANSLATION
Sliding a shape without turning or flipping it.
Describe using: a column vector, e.g. (3, −2) means 3 right and 2 down.
2. REFLECTION
Flipping a shape in a mirror line.
Describe using: the equation of the mirror line (e.g. 'reflection in the line y = 1' or 'reflection in the line 𝑥 = −2').
3. ROTATION
Turning a shape about a fixed point.
Describe using: the angle, the direction (clockwise or anticlockwise), and the centre of rotation.
4. ENLARGEMENT
Making a shape bigger or smaller from a fixed point.
Describe using: the scale factor and the centre of enlargement.
Scale factor > 1: shape gets bigger
0 < SF < 1: shape gets smaller (fractional enlargement)
Negative SF: shape is inverted (on the other side of the centre)