last month, tommy worked at his brother's restaurant for a total of 17 days.he earned 250 a day during weekdays and 350 a day during the weekend.last month,tommy earned 4,850.how many weekdays did he work?
if he worked x weekdays and y weekend days
250x+350y = 4850
since there is no unique solution, start checking.
y=1 x=4500/250 = 18 -- nope, too many days
y=2 x = 4150/250 = 16.6 -- nope, too many days, and x is not an integer.
so keep on checking