Question

Rectangle PQRS is rotated 90° counterclockwise about the origin.

What are the coordinates of point Q’?

Answer 1

Object point Q (x,y) ------------- image point Q'( -y,x)

Explanation:

When a point A (x,y) is rotated 90 degrees counterclockwise about the origin the resulting image of the point is A'(-y,x)

This means first you alternate the positions of x and y coordinates then add a negative sign on the now new y coordinate.

Example a point B(2,3) rotated 90° counterclockwise about the origin will form an image B'(-3,2)

So if point Q (x,y) ------------- image Q'( -y,x)

Substitute real values for (x,y) coordinates to get correct answer.