9514 1404 393
Answer:
rotated vertices are (1, 1), (-2, -1), (-4, 0)
Explanation:
When the rotation direction is not specified, it is usually taken to be counterclockwise. Rotation 270° CCW is the same as rotation 90° CW. The transformation of coordinates is ...
(x, y) ⇒ (y, -x)
Then your rotated points become ...
A(-1, 1) ⇒ A'(1, 1)
B(1, -2) ⇒ B'(-2, -1)
C(0, -4) ⇒ C'(-4, 0)
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In the attached, the rotated triangle is shown in red. As an example, the arc through which point C is rotated is shown.