Answer:
C' (2, -1)
Step-by-step explanation:
C (1, 2) is rotated 90° clockwise
(y,-x)
When a point (x,y) is rotated 90 degree clockwise, the point (x,y)
becomes (y,-x). Interchange the x and y values, multiply x by -1
point rotated 90 degree clockwise (x,y) -> (y,-x)
C (1, 2) is rotated 90° clockwise (1,2) -> (2,-1)
C' (2, -1)