To find the new coordinates of point A (2, 4) after a 270-degree counterclockwise rotation, we can use the rotation transformation formula.
When a point \((x, y)\) is rotated by 270 degrees counterclockwise, the new coordinates \((x', y')\) can be calculated as follows:
\[ x' = y \] \[ y' = -x \]
For point A (2, 4):
- \(x' = y = 4\)
- \(y' = -x = -2\)
Thus, the new coordinates after rotation are (4, -2).
Therefore, the answer is:
(4, -2)