Question

Triangle PQR has its vertices at the following coordinates:

P(5,-4) Q(3,-5) R(1,-1)
Give the coordinates of the image triangle P'Q'R' after a 90° counterclockwise
rotation about the origin.

Answer 1

P'(4, 5) Q'(5, 3) R'(1, 1)

Explanation:

When rotating a point 90 degrees counterclockwise about the origin our point T(x,y) becomes T'(-y,x).