ok so i tried the acos approach and it didnt seem to be working out so i done some research and tried the atan2 function instead with the broken up X & Y values and now works perfectly. thank you so much for your help 
ok so i tried the acos approach and it didnt seem to be working out so i done some research and tried the atan2 function instead with the broken up X & Y values and now works perfectly. thank you so much for your help