The final cost of a bookstore purchase with a $5 coupon in a state that charges 8% sales tax is given by the expression. the variable x represents the amount of the purchase before the sales tax and the coupon is applied.
1.08(x−5)
what does (x−5) represent?
a the cost before applying the coupon
b the rate at which the total cost increases
c the total charge after tax
d the total charge before applying sales tax