first write the coordinates
A (5,8)
B(9,8)
C(9,5)
D(5,5)
to rotate 90 degrees clockwise you must swap coordinates I mean change x for y and change the sign of the secon term or the new y
A(5,8)-->A'(8,-5)
B(9,8)-->B'(8,-9)
C(9,5)-->C'(5,-9)
D(5,5)-->D'(5,-5)
