The side toes of a horse, the pelvis of the whale, and the human appendix are all examples of structures that resemble structures of presumed ancestors, called what?

life would be meaningless without memes

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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