Rewrite to powers of 2 and compare exponents: If 16 × 8^(n+2) = 2^m, find m in terms of n.

Difficulty: Easy

Correct Answer: 3n + 10

Explanation:


Introduction / Context:
Here we convert mixed bases (16 and 8) to a single base 2, then equate exponents. This is a routine indices exercise reinforcing base conversion and exponent addition.


Given Data / Assumptions:

  • 16 × 8^(n+2) = 2^m
  • 16 = 2^4 and 8 = 2^3


Concept / Approach:
Rewrite everything as powers of 2. Add exponents on the left (since same base multiplied), then set the combined exponent equal to m.


Step-by-Step Solution:
16 = 2^48^(n+2) = (2^3)^(n+2) = 2^(3(n+2)) = 2^(3n + 6)LHS = 2^4 × 2^(3n + 6) = 2^(4 + 3n + 6) = 2^(3n + 10)Thus 2^m = 2^(3n + 10) ⇒ m = 3n + 10


Verification / Alternative check:
Plug n = 0: LHS = 16 × 8^2 = 16 × 64 = 1024 = 2^10 ⇒ m = 10, consistent with 3(0)+10.


Why Other Options Are Wrong:
They reflect incorrect coefficient arithmetic (e.g., forgetting the +6 or mis-scaling the 3 on n).


Common Pitfalls:
Expanding 3(n+2) incorrectly or missing the 2^4 factor from 16.


Final Answer:
3n + 10

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