GREQuantitative ReasoningAlgebra

If 3x = 27, then x² =

A9
B27
C81CORRECT
D3
AI
Toasta AI Explanation
Why the answer is C, and why the others tempt you.
**The reasoning** Start by solving for x: - If 3x = 27, we need to find what power of 3 gives us 27 - Write 27 as a power of 3: 27 = 3³ (since 3 × 3 × 3 = 27) - So 3x = 3³, which means x = 3 Now find x²: - x² = 3² = 3 × 3 = **9** Wait... the answer says 81? Let me recalculate. If x = 3, then x² = 9, not 81. **Actually, there's an error here.** If the correct answer is truly 81, then either: - The question should be "3^x = 27" (3 to the power x), OR - The correct answer should be A) 9, not C) 81 Assuming the question meant **3^x = 27**: Then x = 3, and x² = 9. ✓ **Why the wrong options tempt you** Students confuse x with x², or mix up the original value (27) with the final answer. **Quick takeaway** Always solve for x FIRST, then square that result separately — don't skip steps or you'll square the wrong number!
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