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After rotating △ABC 180° about the origin and then reflecting it over the x-axis, what are the coordinates of △A′B′C′?

A. (-3,9), (-4,-3), (4,-3)
B. (3,-9), (4,3), (-4,3)
C. (-3,-9), (-4,3), (4,3)
D. (3,9), (4,-3), (-4,-3)

User TheDrifter
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1 Answer

3 votes

Final answer:

After applying a 180° rotation and a reflection over the x-axis, the coordinates of △A'B'C' are (3, 9), (4, -3), and (-4, -3), which corresponds to Option D.

Step-by-step explanation:

To determine the coordinates of △A'B'C' after a 180° rotation about the origin followed by a reflection over the x-axis, we need to apply two transformations to the coordinates of △ABC. The coordinates given in the options are assumed to represent the original coordinates of △ABC.

A 180° rotation about the origin will change the sign of both the x- and y-coordinates of each point. So if (x, y) are the original coordinates, after the rotation the new coordinates will be (-x, -y). Next, reflecting these new points over the x-axis will change the sign of the y-coordinates but leave the x-coordinates unchanged. Therefore, the final coordinates would be (-x, y).

Applying these transformations:

  • A(-3, 9) becomes A'(3, -9) after rotation and A'(3, 9) after reflection over the x-axis.
  • B(-4, -3) becomes B'(4, 3) after rotation and B'(4, -3) after reflection over the x-axis.
  • C(4, -3) becomes C'(-4, 3) after rotation and C'(-4, -3) after reflection over the x-axis.

So the correct answer is Option D: (3, 9), (4, -3), (-4, -3).

User Krzych
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