Answer:
He can buy up to 20 tickets (ie 20 tickets or less)
The equation is 10+3.25x+5 = 80
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Explanation:
10 = admission cost
3.25 = cost per ticket
x = number of tickets
3.25x = cost from buying x number of tickets
5 = cost of nachos & coke
10+3.25x+5 = total cost of admission, tickets, and food/drink
10+3.25x+5 = 80 since this is the amount he has in his pocket
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Let's solve for x
10+3.25x+5 = 80
3.25x+15 = 80
3.25x = 80-15 .... subtract 15 from both sides
3.25x = 65
x = 65/3.25 ........ divide both sides by 3.25
x = 20
Billy can buy up to 20 tickets (ie 20 tickets or less).