Answer: 9^(x-3) = 9^3
Explanation:
Realizing that 729 = 9^3, we can rewrite the equation ...
9^(x -3) = 729
as ...
9^(x -3) = 9^3 . . . . . . matches the second selection
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Recognizing that 9 = 3^2, a couple of other equivalent forms can be made.
(3^2)^(x -3) = (3^2)^3
3^(2x-6) = 3^6
or, taking the square root, ...
3^(x -3) = 3^3
None of these forms match any answer choices.
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The solution will be found by matching exponents:
x -3 = 3
x = 6