Answer:
[tex]d(c(x))=0.60x-5[/tex]
Step-by-step explanation:
We have been given that a discount store’s prices are 25% lower than department store prices. The function [tex]c(x)=0.75x[/tex] represents the cost (c), in dollars, of an item, where x is the department store price, in dollars.
We are also told that when the item has not sold in one month, the discount store takes an additional 20% off the discounted price and an additional $5 off the total purchase. The function [tex]d(y)=0.85y-5[/tex] represents d, the cost, in dollars, of an item that has not been sold for a month, where y is the discount store price, in dollars.
We are supposed to find the function d(c(x)) that represents the final price of an item when a costumer buys an item that has been in the discount store for a month.
We can see that function d(c(x)) is a composite function. To get our composite function we just need to substitute function c(x) in function d(y).
After making the substitution we will get our desired function as,
[tex]d(c(x))=0.80*(0.75x)-5[/tex]
Upon simplifying our function will be:
[tex]d(c(x))=0.60x-5[/tex]
Therefore, the function [tex]d(c(x))=0.60x-5[/tex] represents the final price of an item when a costumer buys an item that has been in the discount store for a month.