<span>She had $338.86 more in credits than in debits </span>
The graph of the system is
where y= -4x-2 is in red, and y= -4x-5 is in blue.
Given that the lines are parallel, then there is no solution to the system of equations.
80 x 90/100 = 72
Therefore there were 72 milkshakes with whipped cream that were sold.
Answer: no more information?