Answer:
15N + 21
Step-by-step explanation:
We are given that,
Amount of carpet bought by Peter = N meter²
The cost per meter square of the carpet = $15
So, the cost of 'N' meter square of carpet = 15N dollars.
Also, the delivery charge for the carpet = $21
Thus, the total cost of the carpet is given by,
Total cost = Cost per square meter + Delivery charge
i.e. Total cost = 15N + 21 (in dollars).
Hence, the expression representing the cost in dollars is '15N + 21'.