Answer pl you get 10 points bc i selected 15!

The answer would be 13.

To find the atomic mass of a atom, you would add the number of protons and the number of neutrons together. Electrons don't take up much or any of the mass of an atom.

(number of protons) + (number of neutrons) = 7 + 6 = 13

The answer would be 13.

I hope this helps.

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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