Question

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

180°
rotation
180 degrees rotation

−270°
rotation
negative 270 degrees rotation

90°
rotation
90 degrees rotation

−90°
rotation

Answer 1

To determine the rotation that transforms point P (−1, 2) to P′ (2, 1), we can analyze the change in position of the point.

1. Start with the original point P (−1, 2).
2. The new point P′ (2, 1) has coordinates where the x-coordinate increases from −1 to 2 (a change of +3) and the y-coordinate decreases from 2 to 1 (a change of −1).

Next, we review the rotation transformations:
- A **90° clockwise rotation** will transform P (−1, 2) to a point. To find that point, we can use the following transformation:
- If a point (x, y) is rotated 90° clockwise, the new coordinates (x', y') will be (y, -x).
- Here, (−1, 2) becomes (2, 1), which matches P′.

Thus, the rotation that transforms P to P′ is:

**90° rotation clockwise.**

So, among the given options, the correct response is:

**90° rotation** or **90 degrees rotation.**