Question

(a) Write a linear equation to compute the total cost, y, for 1 month if x service calls are made.The linear equation in slope-intercept form is?

Answer 1

The total cost can be model by the equation:

$y=mx+b$

where y is the total cost, x is the number of service calls, m is the cost for each service call and b is the fixed cost.

Plugging the values given in the problem we have that the equation is:

$y=30x+4000$

if we have 135 service calls that means that x=135; plugging this value in the equation fo the cost we have:

$\begin{gathered} y=30(135)+4000 \\ y=8050 \end{gathered}$

Therefore the cost in one month with 135 service calls is $8050