Start making the graph of the situation
from this, we can understand that x is Coreys' initial distance, z is Coreys' final distance, and y will be how many feet had Corey to step back in order to gain a better view.
Using the red triangle we find x through the tan of the given angle
Using the blue triangle we find z through the tan of the given angle the same way as before
finally, find y as the difference between z and x
Corey had to go back 59.71 ft to gain a better view.