One answer is m = 14 and n = 2
Another answer is m = 15 and n = 3
There are infinitely many possible combos
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Explanation:
The rule is
(b^m)/(b^n) = b^(m-n)
We subtract the exponents.
Since we want b^12, this means m-n = 12
Pick any combo of m & n such that they subtract to 12
Here are two combos
m-n = 14-2 = 12
m-n = 15-3 = 12