Which of the following is an extinct animal? 1) tiger
2) penguins
3) panda
4) mammoth

Mammoth is the answer

Mammoth

Explanation:

These were relatives of today's elephants that lived during the last ice age and many of them died when the weather became warmer and their food supply changed

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

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