If $2^{3c + 1} = 2^{10}$, what is the value of $c$?
A$3$
B$\dfrac{10}{3}$
C$\dfrac{9}{3}$
D$4$
Answer & Solution
Correct answer: A. $3$
When the bases are equal (and the base is positive and not 1), the exponents must be equal. So $3c + 1 = 10$.
Solve: $3c = 9 \Rightarrow c = 3$.
Trap B ($10/3$) comes from solving $3c = 10$ — forgetting to subtract the $+1$ first.
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