In a triangle , , and angle . Calculate the area of triangle to 1 decimal place.

Answer and explanation

Correct answer: C.

  1. Step 1: State the sine rule for the area of a general triangle: .
  2. Step 2: Substitute the given side lengths and included angle: .
  3. Step 3: Evaluate using : (to 1 d.p.).
Answer
.
Why not the others: forgets the factor of (); uses instead of ; computes .

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