Mathematics (Core)Exam code: 0580
Transformations
Transformations
The Four Transformations
Object, image and what changes
- The starting shape is the object and the result is the image, with the image's vertices labelled A′, B′, C′ to match A, B, C
- Three of the four keep the shape exactly the same size, so object and image are congruent: reflection, rotation and translation
- Only enlargement changes the size, and even then the shape stays similar
- A point that does not move under a transformation is invariant
- A ruler must be used for every straight edge, which the syllabus states directly
What each transformation needs
| Transformation | What a question can ask for |
|---|---|
| Reflection | a vertical or horizontal mirror line |
| Rotation | a centre at the origin, a vertex, or the midpoint of an edge, through a multiple of 90° |
| Enlargement | positive and fractional scale factors |
| Translation | a column vector |
- Questions never combine two transformations, so each one is described on its own
Exam tip
Name one transformation only
Describing a transformation fully was set in 13 of the 22 papers, and each part of the answer is a separate mark: the name, and each property that goes with it. So write every part even if you doubt one. Never name two transformations: an answer such as "reflection, then translation" scores nothing at all, even when one of them is right.