titik (5,-1) dirotasikn dngn pusat p (2,3) sejauh 90 derjt berlawanan arh putarn jm bayngn titik B adlh..

x' = (x-a) cos m - (y-b) sin m + a
= (5-2) cos 90 - (-1-3) sin 90 + 2
= 4 sin 90 + 2
= 4 + 2 = 6

y' = (x-a) sin m + (y-b) cos m + b
= (5-2) sin 90 + (-1-3) cos 90 + 3
= 3 + 3 = 6

jadi bayangan ttk b (6,6)