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Mathematical Methods · Unit 4 · Trigonometry · Cosine and sine rules

Model and solve problems that involve the sine rule, cosine rule and the area formula in two - and three-dimensional contexts (including bearings, directions and angles of elevation and depression), with and without technology. Mathematical Methods 2025 v1.3

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Question 1

A surveyor measures a triangular plot of land and determines that two sides are $48 \text{ m}$ and $65 \text{ m}$, with the included angle of $52°$. Which of the following is the area of the plot, to the nearest square metre?

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Question 2

A surveyor measures a triangular parcel of land. Two adjacent sides of the triangle measure 85 m and 120 m, and the included angle between them is $42°$. (a) Determine the area of the land parcel, to the nearest square metre. [1 mark] (b) Calculate the third side of the triangle, correct to 1 decimal place. [2 marks]

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