Advanced Math practice question

Answer: 3

Write both sides in base 2: (2²)^x = (2³)^(x − 1) → 2^(2x) = 2^(3x − 3) → 2x = 3x − 3 → x = 3.

Common wrong answers

If you answered 1

1 comes from setting the exponents x and x − 1 equal without converting the bases, which has no solution; 1 is a guess from x − 1 = 0.

If you answered 2

2 comes from 2x = 3(x − 1) solved as 2x = 3x − 1.

If you answered -3

−3 comes from 2x = 3x + 3, mishandling the sign of −3.

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