What happens to an isotope during radioactive decay

during radioactive decay the atoms change. The atomic number in the nucleus changes because of fast moving particles and energy.

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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