Math, I NEED HELP.c:
posted by Izzy. on .
A rental company charges a flat fee of x dollars for a floor sander rental plus y dollars per hour of the rental. One customer rents a floor sander for 4 hours and pays $63. Another customer rents a floor sander for 6 hours and pays $87. Find the flat fee and the cost per hour for the rental and how much it would cost if someone wanted to rent a sander for 11 hours.

D:

equation:
cost = yt + x, where t is the number of hours
case1:
4y + x = 63 > x = 634y
case2:
6y + x = 87 > x = 876y
so 634y = 876y
2y = 24
y = 12
back into 1st equation:
x = 634(12) = 15
cost equation:
cost = 12t + 15
so for 11 hrs
cost = 12(11)+15
= 147