An electrician charges $50 to make a house call and $40 for each hour worked. if you have $200, can you afford a repair that takes 4 hours to complete?

Charge(x) = Electrician's charge as a function of the # of hours worked.

Here,

Charge(x) = $50 + ($40/hour)x

Set this expression = to $200 and solve for x, the number of hours for which the electrician must be paid:

$50 + ($40/hour)x = $200

To solve for x, subtract $50 from both sides: ($40/hr)x = $150.

Then x = 3.75.

You cannot afford to have this 4-hour job done, because your $200 will cover only the house call and the first 3.75 hours.