Difficulty: Easy
Correct Answer: 3√3 cm
Explanation:
Introduction / Context:Converting between area and altitude in an equilateral triangle relies on two linked formulas: A = (√3/4)a^2 and h = (√3/2)a. Use one to find side length, then compute the altitude.
Given Data / Assumptions:
Concept / Approach:First find the side a from A = (√3/4)a^2. Then use h = (√3/2)a to get the altitude.
Step-by-Step Solution:
9√3 = (√3/4) * a^2 ⇒ a^2 = 36 ⇒ a = 6 cmh = (√3/2) * a = (√3/2) * 6 = 3√3 cmVerification / Alternative check:Compute A from a=6: (√3/4)*36 = 9√3 cm^2; consistent.
Why Other Options Are Wrong:
Common Pitfalls:Mixing up the area and altitude formulas or skipping the square on a.
Final Answer:3√3 cm
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