Question

The point P (−1,2)
𝑃

(
−
1
,
2
)
is rotated to become P′ (2,1)
𝑃
′

(
2
,
1
)
. Describe the rotation by degree and direction.(1 point)
Responses

180°
180
°
rotation
180 degrees rotation

−270°
−
270
°
rotation
negative 270 degrees rotation

90°
90
°
rotation
90 degrees rotation

−90°
−
90
°
rotation

Answer 1

Rotation by -90° (90° clockwise).
Check: a 90° clockwise rotation sends (x,y) → (y,−x), so (−1,2) → (2,1).