EXERCISE (TRIGONOMETRY)
The Sine Rules
1. Solve triangle ABC if A = 320.0⁰, B = 81.8⁰, a = 42.9cm
2. Ameer wishes to measure the distance across the Sungai Sarawak. He determines that C =
112.90⁰, A = 31.10⁰ and b = 347.6 ft. Find the distance a across the river. See Figure 3.
3. Two ranger stations are on an east-west line 110 miles apart. A forest fire is located on a
bearing of N 42° E from the western station at A and a bearing of N 15° E from the eastern
station at B. How far is the fire from the western station? (See Figure 4.)
4. Find the length of each side a. Do not use a calculator.
Determine the remaining sides and angles of each triangle ABC.
The Cosine Rules
1. Solve triangle ABC if A = 42.3⁰, b = 12.9 m and c = 15.4 m. See Figure 13.
2. Solve triangle ABC if a = 9.47 ft, b = 15.9 ft, and c = 21.1 ft.
3. Find angle B for the triangle shown in Figure 14(b).
Solve each triangle. Approximate the values to the nearest tenth.
Solve each triangle.