The properties of being make a diamond a gemstone

rare and beautiful

Explanation:

Diamond, also called gemstone, is a gemstone formed by pure carbon atoms in crystallizing conditions. It can be found all over the Earth's surface and has high market value and is considered one of the most valuable gems. Diamond is the most valued gemstone in the gemstone trade and its gem is used for making luxury jewelry. Although it has the same composition as graphite, what makes a diamond a gemstone is its ability to be a rare and beautiful stone.

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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