To find the coordinates of a point \(D\) after a 90-degree counterclockwise rotation about the origin, we can use the following transformation for point \((x, y)\):
\[ (x', y') = (-y, x) \]
This means that if point \(D\) has original coordinates \((x_D, y_D)\), after rotation, the new coordinates \((x', y')\) will be:
\[ x' = -y_D \] \[ y' = x_D \]
If you provide the original coordinates of point \(D\), I can help you calculate the new coordinates after the rotation.
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