Answer:
The fixed amount that is charged is:
$ 80
Step-by-step explanation:
We are given a straight line joins the ordered pairs (0,80) and (4,240).
We know that the equation of a line passing through two points (a,b) and (c,d) is calculated by:
Here we have:
(a,b)=(0,80) and (c,d)=(4,240)
Hence, the equation of line is:
Hence, the fixed charge is the initial charge i.e. when the number of days i.e. x value is zero.
Hence, when x=0 we have:
y=80
Hence, the fixed charge is: 80