Translation and reflection
Sliding a shape (translation) and mirroring it (reflection) on a coordinate grid. Year 5/6.
Translation slides a shape without rotating or flipping; reflection mirrors it across a line. Year 5 introduces both; Year 6 SATs test translation by vector (e.g. ‘3 right, 2 down’) and reflection across the x or y axis.
Worked examples
Translate (3, 2) by ‘4 right, 1 down’: new point (7, 1).
Reflect (3, 2) in the y-axis: (−3, 2). The y-coordinate stays; the x-sign flips.
Reflect a triangle in the x-axis: each vertex gets its y-coordinate negated.
Frequently asked questions
Why does only one coordinate change in a reflection?
Reflecting in the x-axis flips up-down → only y changes sign. Reflecting in the y-axis flips left-right → only x changes sign.
Translation vs rotation?
Translation slides; rotation turns around a point. Year 6 introduces rotation; KS3 covers all angle rotations.