Advanced Math practice question

Answer: 2

Set 3ˣ = 9: since 9 = 3², the crossing is at x = 2.

Common wrong answers

If you answered 3

3³ = 27; the needed power is 3² = 9.

If you answered 9

9 is the value 3ˣ must reach, not the exponent.

If you answered -9

−9 is the constant being subtracted; the graph crosses the x-axis where 3ˣ = 9, at x = 2.

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