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Please answer which choice it is!! geometry 9-10th grade level!

Please answer which choice it is!! geometry 9-10th grade level!-example-1

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If the point (x, y) is rotated around the origin 90 degrees then its image is (-y, x)

We consider that 90 degrees mean +90 which means rotating anticlockwise

Since point A is (-2, 1)

Change the sign of y-coordinate and switch the 2 coordinates

A' = (-1, -2)

Answer D

(x, y) rotating by 180 degrees, then its image is (-x, -y) just opposite the signs of the coordinates

(x, y) rotating 270 degrees, then its image is (y, -x), change the sign of x-coordinate and switch the 2 coordinates

All of these rules for rotating anticlockwise (+ve angles)

This is a symmetry for rotation

•If the point (x, y) rotated about the origin by angle 90° counterclockwise, then its image is (-y, x)

•If the point (x, y) rotated about the origin by angle 180° counterclockwise, then its image is (-x, -y)

•If the point (x, y) rotated about the origin by angle 270° counterclockwise, then its image is (y, -x)

•If the point (x, y) rotated about the origin by angle 90° clockwise, then its image is (y, -x)

•If the point (x, y) rotated about the origin by angle 180° clockwise, then its image is (-x, -y)

•If the point (x, y) rotated about the origin by angle 270° clockwise, then its image is (-y, x)

•There is no difference between rotating 180° clockwise or counterclockwise around the origin

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