Question

The point D(2, -5) is rotated 90° counterclockwise around the origin. What are the coordinates of the resulting point, D′?

Answer 1

D' = (5, 2)

Explanation:

Try to join D and the origin using a line. Counterclockwise means in an opposite direction of rotation of the clock hands. So draw another line towards the right which is perpendicular to the previous line to fine the answer. Remember the length of the lines should be equal.