Calculate the area of an equilateral triangle whose side length measures 6 cm.
Answer and explanation
Correct answer: D. 9 * sqrt(3) cm^2
- Step 1: Area formula for equilateral triangle: Area = [sqrt(3) / 4] a^2. Step 2. Substitute a = 6: Area = [sqrt(3) / 4] 36 = 9 sqrt(3) cm^2. Answer: 9 sqrt(3) cm^2. Why not the others:* 18 sqrt(3) divides by 2 instead of 4; 12 * sqrt(3) uses a = 8; 36 cm^2 is a^2 alone.
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