Why do the atoms in most solids move more slowly than those in liquids?

atoms are incredibly small and cannot be seen with even the most powerful light microscope

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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