3. Rotations
Sign In
When a point with coordinates (x,y) is rotated 180^(∘) clockwise about the origin, the coordinates of its image are (- x,- y).
Graph:
Coordinates: X'(-3,1), Y'(- 5,4), Z'(- 1,5)
A rotation is a transformation about a fixed point called center of rotation. Each point of the original figure and its image are the same distance from the center of rotation. When a clockwise rotation is performed about the origin, the coordinates of the image can be written in relation to the coordinates of the preimage.
Rotations About the Origin | ||
---|---|---|
90^(∘) Rotation | 180^(∘) Rotation | 270^(∘) Rotation |
ccc Preimage & & Image [0.5em] (x,y) & → & (y,- x) |
ccc Preimage & & Image [0.5em] (x,y) & → & (- x,- y) |
ccc Preimage & & Image [0.5em] (x,y) & → & (- y,x) |