Question

A furniture rental company charges a fixed amount plus a fee based on the number of days for which the furniture is rented. The graph below shows the amount paid for a different number of days to rent the furniture: A graph titled Furniture Rentals plots the Number of Days on the x axis and the Amount in dollars on the y axis. A straight line joins the ordered pairs 0, 80 and 4, 240. What is the fixed amount charged? $20 $40 $60 $80

Answer 1

The fixed amount that is charged is:

$ 80

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:

`y-b=(d-b)/(c-a)* (x-a)`

Here we have:

(a,b)=(0,80) and (c,d)=(4,240)

Hence, the equation of line is:

`y-80=(240-80)/(4-0)* (x-0)\\\\\\y-80=(160)/(4)* x\\\\\\y-80=40x\\\\y=40x+80`

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

Answer 2

The fixed amount is the amount charged for 0 days' rental. The ordered pair (0, 80) tells you it is $80.