Let s represent the length of the second side. Then the length of the first side is 3s and the length of the third side is s+13. The perimeter is the sum of side lengths:
D. Since we know that 1 ticket = $8 we would multiply to figure out how much 7 tickets were. (7x$8). And to figure out his change you would subtract the ticket amount from $100 :) Hope this helps
