Describe the transformation in the diagram.

B (-3, -1) A (-4, -2) C (-1, -2)
B' (1, -3) A' (2, -4) C' (2, -1)
A. 90 degrees clockwise rotation about the origin
B. 90 degrees counterclockwise rotation about the origin
C. 270 degrees counterclockwise rotation about the origin
D. 180 degrees counterclockwise rotation about the origin

1 answer

To determine the transformation between the points A, B, C and their transformed points A', B', C', we will analyze each point.

The original points are:

  • A (-4, -2)
  • B (-3, -1)
  • C (-1, -2)

The transformed points are:

  • A' (2, -4)
  • B' (1, -3)
  • C' (2, -1)

Analysis of transformation:

  1. Point A (-4, -2) to A' (2, -4):

    • The transformation involves changes in coordinates:
    • The x-coordinate changes from -4 to 2 (a change of +6).
    • The y-coordinate changes from -2 to -4 (a change of -2).
  2. Point B (-3, -1) to B' (1, -3):

    • The x-coordinate changes from -3 to 1 (a change of +4).
    • The y-coordinate changes from -1 to -3 (a change of -2).
  3. Point C (-1, -2) to C' (2, -1):

    • The x-coordinate changes from -1 to 2 (a change of +3).
    • The y-coordinate changes from -2 to -1 (a change of +1).

Determine Transformation Type:

To check the possibility of 90 degrees rotation:

  • A point (x, y) after a 90 degrees clockwise rotation about the origin transforms to (y, -x).
  • A point (x, y) after a 90 degrees counterclockwise rotation about the origin transforms to (-y, x).

Now, let’s analyze:

  1. For A:
    • Original A (-4, -2):
      • For 90 degrees clockwise: A would move to (-2, 4) — this is not A'.
      • For 90 degrees counterclockwise: A would move to (2, -4) — this matches A'.
  2. For B:
    • Original B (-3, -1):
      • For 90 degrees clockwise: B would move to (-1, 3) — this does not match B'.
      • For 90 degrees counterclockwise: B would move to (1, -3) — this matches B'.
  3. For C:
    • Original C (-1, -2):
      • For 90 degrees clockwise: C would move to (-2, 1) — this does not match C'.
      • For 90 degrees counterclockwise: C would move to (2, -1) — this matches C'.

Since all original points match their transformed counterparts consistently only for a 90 degrees counterclockwise rotation, the transformation described in the diagram is:

Answer: B. 90 degrees counterclockwise rotation about the origin.