Year 11 Trigonometry (Finding Sides) Worksheet — Level 1 — Practice Set 2 — Answers
Answer sheet with worked solutions for the Year 11 trigonometry worksheet.
Year 11 Trigonometry (Finding Sides) Worksheet — Level 1 — Practice Set 2 — Answers
Label the sides (opposite, adjacent, hypotenuse), choose the ratio (SOH CAH TOA), then solve.
1.In a right-angled triangle, the hypotenuse is 27 cm and one angle is 70°. Find the side opposite the 70° angle, to 1 decimal place.
Answer: 25.4 cm
- sin 70° = opposite ÷ hypotenuse
- opposite = 27 × sin 70°
- ≈ 25.4
2.In a right-angled triangle, the hypotenuse is 10 cm and one angle is 41°. Find the side opposite the 41° angle, to 1 decimal place.
Answer: 6.6 cm
- sin 41° = opposite ÷ hypotenuse
- opposite = 10 × sin 41°
- ≈ 6.6
3.In a right-angled triangle, the hypotenuse is 11 cm and one angle is 67°. Find the side opposite the 67° angle, to 1 decimal place.
Answer: 10.1 cm
- sin 67° = opposite ÷ hypotenuse
- opposite = 11 × sin 67°
- ≈ 10.1
4.In a right-angled triangle, the hypotenuse is 18 cm and one angle is 67°. Find the side opposite the 67° angle, to 1 decimal place.
Answer: 16.6 cm
- sin 67° = opposite ÷ hypotenuse
- opposite = 18 × sin 67°
- ≈ 16.6
5.In a right-angled triangle, the hypotenuse is 9 cm and one angle is 27°. Find the side opposite the 27° angle, to 1 decimal place.
Answer: 4.1 cm
- sin 27° = opposite ÷ hypotenuse
- opposite = 9 × sin 27°
- ≈ 4.1
6.In a right-angled triangle, the hypotenuse is 15 cm and one angle is 59°. Find the side opposite the 59° angle, to 1 decimal place.
Answer: 12.9 cm
- sin 59° = opposite ÷ hypotenuse
- opposite = 15 × sin 59°
- ≈ 12.9
7.In a right-angled triangle, the hypotenuse is 14 cm and one angle is 54°. Find the side opposite the 54° angle, to 1 decimal place.
Answer: 11.3 cm
- sin 54° = opposite ÷ hypotenuse
- opposite = 14 × sin 54°
- ≈ 11.3
8.In a right-angled triangle, the hypotenuse is 6 cm and one angle is 34°. Find the side opposite the 34° angle, to 1 decimal place.
Answer: 3.4 cm
- sin 34° = opposite ÷ hypotenuse
- opposite = 6 × sin 34°
- ≈ 3.4
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