Difficulty: Easy
Correct Answer: 16√3 cm2
Explanation:
Introduction / Context:The area of an equilateral triangle can be computed directly from side length using a fixed constant multiplier. This avoids trigonometric detours and emphasizes formula recall and clean substitution with units carried consistently.
Given Data / Assumptions:
Concept / Approach:Substitute a = 8 into A = (√3/4)a^2. Since a^2 = 64, the product streamlines neatly. Reporting the exact radical form (rather than decimals) keeps precision and matches typical aptitude answer formats.
Step-by-Step Solution:
Compute a^2: 8^2 = 64.Apply formula: A = (√3/4) * 64 = 16√3 cm^2.Approximate (optional): √3 ≈ 1.732 ⇒ A ≈ 27.712 cm^2.Verification / Alternative check:
Using height h = (√3/2)a = 4√3 ⇒ A = (1/2)*base*height = (1/2)*8*(4√3) = 16√3 cm^2.Why Other Options Are Wrong:
Common Pitfalls:
Final Answer:16√3 cm2.
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