Question

An electrician charges $35 per hour plus a fixed amount for residential work. For a job that took 6 hours, he billed $270. Write an equation in the form y = mx + b that represents the cost, c, of hiring this electrician for a job that takes x hours.

Answer 1

With the information provided, we can begin with the equation:

y=35x + b

With x = number of hours, y = total cost, b = fixed amount that is charged for residential work

We know that after 6 hours, $270 was charged:

$270 = $35(6) + b

Solve for b:

b = $270 - $210 = $60

The fixed amount that is charged for residential work is $60. So now we can rewrite the equation as:

y = 35x + 60