COO018 · Coordinate geometry · Classes 9–12
Transformations coordinates
Coordinate transformations move points by rules: a translation adds (dx, dy); a 90° anticlockwise rotation about O sends (x, y) to (−y, x).
T, RTransformations coordinates
📐 Formula
T: (x, y) → (x + dx, y + dy); R₉₀: (x, y) → (−y, x)
✏️ Worked example
(1, 2) translated by (2, 1) is (3, 3); rotated 90° it becomes (−3, 3).
🌍 Where it is used
Computer graphics, animation, robotics.
❓ Quick check
Rotate (2, 0) by 90° anticlockwise about O.
🏋️ Practice
EasyTranslate (−1, 4) by (3, −2).
Answer: (2, 2)
MediumRotate (1, 3) by 180°.
Answer: (−1, −3)
ChallengeRotate (4, 1) by 90° anticlockwise.
Answer: (−1, 4)