Tomas’s math class held a raffle. The student who picked the ticket with a pair of equivalent equations on it would win. Which is the winning ticket?


x squared minus 3 x y + 4 minus 2 x squared = negative x squared minus 2 x y minus x y + 4

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7 y squared minus y z + 4 minus 2 y z = 7 y squared minus 2 y z + 4 y z.

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3 a squared minus a b + 3 minus 3 a b = 6 a squared minus 2 a b + 3 minus 2 a b

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9 s squared minus s t + 5 minus 3 s t = 6 s squared minus 3 s t + 5 + 3 s squared