Answer:
<h2>$12 - t</h2>
Step-by-step explanation:
(the cost of the snack) + (the cost of the ticket) = (the total cost)
the cost of tickets = <em>t</em>
the total cost = <em>$12</em>
(the cost of the snack) = (the total cost) - (the cost of the ticket)
Substitute
(the cost of the snack) = <em>$12 - t</em>