If $3^{2x} = 81$, what is the value of $x$?
A$3$
B$1$
C$2$
D$4$
Answer & Solution
Correct answer: C. $2$
$81 = 3^{4}$. So $3^{2x} = 3^{4} \Rightarrow 2x = 4 \Rightarrow x = 2$.
- Trap D ($4$) reads off the exponent of $81$ without dividing.
- Trap A and C miscount.
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