Answer:
On Tuesday
591 burgers are sold.
Some are hamburgers and some are cheeseburgers.
59 fewer cheeseburgers sold than hamburgers.
Number of cheeseburgers --> x
Number of hamburgers --> y
x+y= 591 --> x = 591-y
x = y-59
so
591-y = y-59
-2y = -650
y = 325
so
x = 325-59
x =266