Digital PSAT Math Practice Question 307: Answer and Explanation

Question: 307

4xⁿ + x⁴ⁿ =

• A. 5x5n
• B. xⁿ(4 + x³ⁿ)
• C. 5x⁴ⁿ²
• D. 4xⁿ(1 + x³ⁿ)

Correct Answer: B

Explanation:

(B) Factor an $x^n$ out of the expression to get the answer:

You cannot combine $x^n$ and $x^{4n}$ into one term because they are not raised to the same power.