A point is rotated about the origin. Its coordinates are P(−4,10) and P′(−10,−4). Determine the degree of rotation and direction by applying rotation mapping.(1 point)

Responses

270 degrees (counterclockwise)
270 degrees (counterclockwise)

−180 degrees (clockwise) or 180 degrees (counterclockwise)
negative 180 degrees (clockwise) or 180 degrees (counterclockwise)

−90 degrees (clockwise)
negative 90 degrees (clockwise)

90 degrees (counterclockwise)

1 answer

To determine the degree and direction of rotation of point P(−4, 10) to point P′(−10, −4) about the origin, we can apply the concept of rotation mapping.

  1. Finding the angle of rotation: We start with the original point P(−4, 10) and see how it transforms into point P′(−10, −4).

  2. Understanding the rotation transformation: A rotation in a 2D plane about the origin can be represented using rotation matrices or geometric reasoning.

    • A 90 degrees counterclockwise rotation transforms coordinates (x, y) to (-y, x).
    • A 90 degrees clockwise rotation transforms (x, y) to (y, -x).
    • A 180 degrees rotation transforms (x, y) to (-x, -y).
    • A 270 degrees counterclockwise rotation or a 90 degrees clockwise rotation switches the transformations.
  3. Translating the coordinates: Let's check how point P(−4, 10) would be positioned if we rotated it through the various degrees:

    • 90 degrees counterclockwise: \[ (−4, 10) \rightarrow (−10, −4) \] This matches the point P′.

This means the transformation from P to P′ is indeed a 90-degree counterclockwise rotation.

Thus, the degree of rotation is 90 degrees counterclockwise.

Therefore, the correct choice is:

90 degrees (counterclockwise).