Question

An appliance company uses the function f
h. = 40h + 120 to calculate the total repair bill, f
h. , for h number of hours worked. Find h if f
h. = $200.

Answer 1

fh. = 40h + 120,  fh. = $200

200 = 40h + 120
200 - 120 = 40h
80 = 40h
 80/40  = h
  2 = h

h = 2 hours.