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What are the coordinates of R when rotated about the origin by:

a) 90 clockwise
b) 180
c) 270 clockwise

What are the coordinates of R when rotated about the origin by: a) 90 clockwise b-example-1

1 Answer

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The coordinates of R when rotated about the origin by 90 degrees clockwise, 180 degrees, and 270 degrees clockwise are (-3, 4), (-4, -3), and (3, -4), respectively.

When rotating a point about the origin, we can use the following rotation matrices:

90 degrees clockwise: [[0, -1], [1, 0]]

180 degrees: [[-1, 0], [0, -1]]

270 degrees clockwise: [[0, 1], [-1, 0]]

To rotate point R about the origin, we simply multiply its coordinates by the corresponding rotation matrix.

a) 90 degrees clockwise

R = (4, 3)

R_rotated = [[0, -1], [1, 0]] * R

R_rotated = (-3, 4)

b) 180 degrees

R = (4, 3)

R_rotated = [[-1, 0], [0, -1]] * R

R_rotated = (-4, -3)

c) 270 degrees clockwise

R = (4, 3)

R_rotated = [[0, 1], [-1, 0]] * R

R_rotated = (3, -4)

Therefore, the coordinates of R when rotated about the origin by 90 degrees clockwise, 180 degrees, and 270 degrees clockwise are (-3, 4), (-4, -3), and (3, -4), respectively.

Image confirmation

The image you provided confirms the above calculations. When point R is rotated 90 degrees clockwise, it moves to the point (-3, 4).

When it is rotated 180 degrees, it moves to the point (-4, -3). And when it is rotated 270 degrees clockwise, it moves to the point (3, -4).

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