Answer: The customer will pay $17.35 for the shirt.
Step-by-step explanation: Given that a shirt costs $19.85 and a customer has a coupon that will save her $2.50 on the price of the shirt.
We are to find the amount that the customer will pay for the shirt.
Given that
the original cost of the shirt = $19.85
and
the price that the customer save by using coupon = $2.50.
Therefore, the total cost that the customer will pay for the shirt is given by

Thus, the customer will pay $17.35 for the shirt.