Answer:
c = (y-0.13y)(1.08)
Explanation:
c = cost and y = the original price
The amount of money off is 13% of y, or 0.13 of y. You would subtract that from y to get the price of the cards with the discount. For final cost, you need the cost of the cards (1) plus the cost of tax (8%, or 0.08). 1+0.08 is 1.08, so that's what you would multiply y by to get the final cost of the cards.
Hope this helped!