Multiple choice general knowledge math & puzzles If X^4 = 16 , what is 4^x = ? 16 2 4 8 Reveal answer Fill a bubble to check yourself A Correct answer Explanation If x^4 = 16, then x = 2 (since 2*2*2*2 = 16). Substituting x = 2 into the second expression, 4^x becomes 4^2, which equals 16.