Dylan bought 3 identical shirts online for a total cost of $71.83 including a flat rate (one time fee) of $7.99 for shipping. What equation can be used to determine the cost, s, of one shirt?
3s + 7.99 = 71.83
3 - 7.99s = 71.83
3 + 7.99s = 71.83
3s - 7.99 = 71.83