Advanced Math practice question

Answer: A. x = y

8^y = (2³)^y = 2^(3y). So 2^(3x) = 2^(3y), which means 3x = 3y and x = y.

Why the other answers are wrong

B. x = 3y

x = 3y would give 2^(9y) on the left.

C. y = 3x

y = 3x would give 8^(3x) = 2^(9x) on the right.

D. x = y + 3

Adding 3 to y has no relation to the factor of 3 in the base.

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