In triangle ABC, AB = 8 cm, AC = 6 cm and angle A = 60 degrees. Find the area of the triangle.
Answer and explanation
Correct answer: C. 12 root 3 cm2
- Step 1: Area = 1/2 x AB x AC x sin A. Step 2. = 1/2 x 8 x 6 x (root 3 / 2) = 12 root 3 cm2. Answer: 12 root 3 cm2. Why not the others: 24 cm2: That uses 1/2 x 8 x 6 but leaves out the sine of the angle. 24 root 3 cm2: That forgets the factor 1/2. 12 cm2: That uses sin 60 as 1/2, which is the value of sin 30.
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