Advanced Math practice question

Answer: 3

4ˣ + 4ˣ = 2 · 4ˣ = 2 · 2^(2x) = 2^(2x + 1). So 2x + 1 = 7 and x = 3.

Common wrong answers

If you answered 6

6 comes from 2x = 7 − 1 solved as x = 6.

If you answered 7

7 is the exponent on the right, not x.

If you answered 3.5

3.5 comes from 2x = 7, forgetting the factor 2 from adding the two terms.

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