Question

The point P (−1,2)
is rotated to become P′ (2,1)
. Describe the rotation by degree and direction.(1 point)
Responses

−270°
rotation
negative 270 degrees rotation

180°
rotation
180 degrees rotation

90°
rotation
90 degrees rotation

−90°
rotation

Answer 1

Rotation of −90° (clockwise 90°) about the origin.

Check: the −90° rotation sends (x,y) → (y,−x), so (−1,2) → (2,1).