After rotating a point C 90° counterclockwise about the origin the coordinates of C' would be (-2, 1)
In this question, we have been given a triangle ABC.
A point C is at (1, 2)
The triangle is rotated counter clockwise 90° about the origin.
We need to find the coordinates of C' which is image of vertex C after rotation.
We know that, if we rotate a point 90° counterclockwise about the origin a point (x, y) becomes (-y, x).
Here C(1, 2) is rotated 90 degrees counterclockwise about the origin.
So, the coordinates of C' would be,
C' = (-2, 1)
Therefore, after rotating a point C 90° counterclockwise about the origin the coordinates of C' are (-2, 1)
Learn more about the rotation here:
brainly.com/question/2763408
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