Interpreting Expressions

Question

a plumber charges a flat fee for each job, plus an hourly rate for the number of hours the job takes to complete. The total cost of the job, in dollars, can be modeled by the equation y=50+65x

 

What does the independent variable in the expression represent in this situation?

A. the number of jobs, y
B. the number of hours to complete the job, x
C. the cost per hour, $65
D. the total cost for the job, y

What does the coefficient in the expression represent in this situation?
A. the number of hours to complete the job, x
B. the cost per hour, $65
C. the flat fee, $65
D. the flat fee, $50

What does the constant term in the expression represent in this situation?
A. the number of jobs, x
B. the cost per hour, $65
C. the cost per hour, $50
D.the flat fee, $50

 

What does the dependent variable in the expression represent in this situation?
A. the number of jobs, y
B. the number of hours to complete the job, x
C. the total cost for the job, y
D. the flat fee, $65

Answer 1

If I charged $25 per hour for working on a car plus a flat fee of $50 for the appointment the cost equation would be:

 

y = 25x + 50

 

The independent variable, x, represents the number of hours of work.

 

The coefficient, 25, represents the charge per hour

 

The constsnt, 50, represents the flat fee

 

The dependent variable, y, represents the total cost for the job

Answer 2

1. What number does not change in the equation?