Ask questions and get helpful answers.

Dan works at a hardware store. The employee discount is determined by the

formula d = 0.15 (c − 10 ). Use the inverse of this function to find the cost of the item for which Dan received an $18.00 discount.
a. Find the inverse function that models cost as a function of the discount.
b. Evaluate the inverse function for d = 18.
c. What was Dan’s final cost for this item?

  1. 👍
  2. 👎
  3. 👁
  4. ℹ️
  5. 🚩

1 answer

  1. I don't think you are using the concept of the "inverse of a function" in the proper way, you are just solving the equation for c

    d = .15c - 1.5
    .15c = d + 1.5
    c = (d+1.5)/.15

    now plug in d = 18
    c = (18+1.5)/.15 = 130

    We could have just plugged in d = 18 in the original

    18 =.15(c-10)
    18/.15 = c-10
    120 = c - 10
    130 = c

    1. 👍
    2. 👎
    3. ℹ️
    4. 🚩

Answer this Question

Related Questions

Still need help?

You can ask a new question or browse existing questions.