Advanced Math practice question

Answer: 4

Set 2ˣ − 3 = 13, so 2ˣ = 16. Since 16 = 2⁴, x = 4.

Common wrong answers

If you answered 5

5 comes from 2ˣ = 32 — adding 3 to 13 gives 16, not 32. Or perhaps 2⁵ was confused with 16; 2⁴ = 16.

If you answered 8

8 is 16 / 2, treating 2ˣ as 2 times x. The x is an exponent: 2ˣ = 16 means x = 4.

If you answered 13

13 is the target VALUE of g(x), not the input x. Solve 2ˣ = 16.

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