Which of the following is the image of the point (-1,6) after a counterclockwise rotation of 90 degrees about the point (4,2)

Question

(1) (8,7)

(2) (3,8)

(3) (-5,-3)

(4) (0,-3)

Answer 1

Offset (-1,6) by (4,2) to get (-1-4,6-2) = (-5,4).

90 degree CCW rotation of (x,y) give (-y,x), so 90 CCW rotation of (-5,4) gives (4,5)

Restore (4,2) offset:

(4+4, 5+2) = (8.7)