A triangular plot of land has two adjacent sides measuring and , forming an included angle of . What is the area of this land?

Answer and explanation

Correct answer: C.

  1. Step 1: Use the sine formula for triangle area: .
  2. Step 2: Substitute , , and , noting that : .
Answer
.
Why not the others: forgets the factor of in the area formula; omits entirely, calculating ; mistakenly sets .

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