To find the coordinates of the point E(5, 3) after a 90° counterclockwise rotation about the origin, we use the rotation transformation formula for a point (x, y):
\[ (x', y') = (-y, x) \]
For the point E(5, 3):
- The x-coordinate is 5 and the y-coordinate is 3.
- Applying the formula:
\[ (x', y') = (-3, 5) \]
Thus, the coordinates of E' after the rotation are:
\[ E'(−3, 5) \]
So, the coordinate of E′ is \((-3, 5)\).