Year 12 Trigonometry (Finding Sides) Worksheet — Level 2 — Practice Set 3 — Answers
Answer sheet with worked solutions for the Year 12 trigonometry worksheet.
Year 12 Trigonometry (Finding Sides) Worksheet — Level 2 — Practice Set 3 — Answers
Label the sides (opposite, adjacent, hypotenuse), choose the ratio (SOH CAH TOA), then solve.
1.In a right-angled triangle, the side adjacent to a 24° angle is 14 m. Find the opposite side, to 1 decimal place.
Answer: 6.2 m
- tan 24° = opposite ÷ adjacent
- opposite = 14 × tan 24°
- ≈ 6.2
2.In a right-angled triangle, the side adjacent to a 52° angle is 11 m. Find the opposite side, to 1 decimal place.
Answer: 14.1 m
- tan 52° = opposite ÷ adjacent
- opposite = 11 × tan 52°
- ≈ 14.1
3.In a right-angled triangle, the hypotenuse is 8 cm and one angle is 58°. Find the side opposite the 58° angle, to 1 decimal place.
Answer: 6.8 cm
- sin 58° = opposite ÷ hypotenuse
- opposite = 8 × sin 58°
- ≈ 6.8
4.In a right-angled triangle, the hypotenuse is 22 cm and one angle is 26°. Find the side adjacent to the 26° angle, to 1 decimal place.
Answer: 19.8 cm
- cos 26° = adjacent ÷ hypotenuse
- adjacent = 22 × cos 26°
- ≈ 19.8
5.In a right-angled triangle, the side adjacent to a 37° angle is 19 m. Find the opposite side, to 1 decimal place.
Answer: 14.3 m
- tan 37° = opposite ÷ adjacent
- opposite = 19 × tan 37°
- ≈ 14.3
6.In a right-angled triangle, the hypotenuse is 27 cm and one angle is 53°. Find the side adjacent to the 53° angle, to 1 decimal place.
Answer: 16.2 cm
- cos 53° = adjacent ÷ hypotenuse
- adjacent = 27 × cos 53°
- ≈ 16.2
7.In a right-angled triangle, the side adjacent to a 68° angle is 17 m. Find the opposite side, to 1 decimal place.
Answer: 42.1 m
- tan 68° = opposite ÷ adjacent
- opposite = 17 × tan 68°
- ≈ 42.1
8.In a right-angled triangle, the hypotenuse is 19 cm and one angle is 35°. Find the side opposite the 35° angle, to 1 decimal place.
Answer: 10.9 cm
- sin 35° = opposite ÷ hypotenuse
- opposite = 19 × sin 35°
- ≈ 10.9
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