8th Grade · Geometry
Angle of Rotation
8.G.A.3
Definition
The number of degrees a figure is turned about the center of rotation. Common angles include 90, 180, and 270 degrees.
Examples
- A 180-degree rotation about the origin sends (x,y) to (-x,-y).
- Counterclockwise is positive; clockwise is negative.
Key rule
The angle of rotation tells how far the figure turns.
Memory hook
How many degrees it spins.