a repair person charges a travel fee to visit a home and an hourly fee for the time spent fixing a leak. a repair that takes 2hours cost $100 a repair that takes 6hours cost $260

write an equation to represent the total cost of a repair,y, as a function of the number of hours spent fixing a leak, x.

1 answer

To find an equation that represents the total cost of a repair \( y \) as a function of the number of hours spent fixing a leak \( x \), we can analyze the given information and calculate the travel fee and the hourly rate.

  1. Let \( t \) be the travel fee and \( r \) be the hourly rate.

  2. From the problem, we have two scenarios:

    • For a repair that takes 2 hours, the total cost is $100: \[ y = t + 2r = 100 \quad \text{(1)} \]
    • For a repair that takes 6 hours, the total cost is $260: \[ y = t + 6r = 260 \quad \text{(2)} \]
  3. We can solve these two equations to find the values of \( t \) and \( r \).

    • From equation (1): \[ t + 2r = 100 \quad \text{(1)} \]
    • From equation (2): \[ t + 6r = 260 \quad \text{(2)} \]
  4. We can subtract equation (1) from equation (2): \[ (t + 6r) - (t + 2r) = 260 - 100 \] \[ 4r = 160 \] \[ r = 40 \]

  5. Now, substitute \( r = 40 \) back into equation (1) to find \( t \): \[ t + 2(40) = 100 \] \[ t + 80 = 100 \] \[ t = 20 \]

  6. Now we have:

    • Travel fee \( t = 20 \)
    • Hourly rate \( r = 40 \)
  7. The total cost of a repair as a function of the number of hours \( x \) can be expressed as: \[ y = t + rx \] Substituting the values of \( t \) and \( r \): \[ y = 20 + 40x \]

Thus, the equation representing the total cost \( y \) as a function of the number of hours \( x \) spent fixing a leak is: \[ y = 20 + 40x \]