Difficulty: Easy
Correct Answer: 4 cm
Explanation:
Introduction / Context:Equilateral triangle area depends solely on side length via a constant factor. Inverting the standard formula lets us find side length directly from a given area, reinforcing comfort with algebraic manipulation and radicals.
Given Data / Assumptions:
Concept / Approach:Set 4√3 = (√3/4) * a^2 and solve for a^2 by isolating it. Cancel √3 on both sides to simplify early and avoid handling nested radicals later. Take the positive square root because side length is positive.
Step-by-Step Solution:
4√3 = (√3/4) * a^2.Multiply both sides by 4/√3 ⇒ a^2 = 4√3 * (4/√3) = 16.Therefore, a = √16 = 4 cm.Verification / Alternative check:
Plug back: (√3/4)*4^2 = (√3/4)*16 = 4√3 cm^2, matching the given area.Why Other Options Are Wrong:
Common Pitfalls:
Final Answer:4 cm.
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