11th Grade Trigonometry (Finding Sides) Worksheet — Level 3 — Practice Set 3 — Answers
Answer sheet with worked solutions for the 11th Grade trigonometry worksheet.
11th Grade Trigonometry (Finding Sides) Worksheet — Level 3 — Practice Set 3 — Answers
Label the sides (opposite, adjacent, hypotenuse), choose the ratio (SOH CAH TOA), then solve.
1.In a right triangle, the hypotenuse is 17 cm and one angle is 41°. Find the side opposite the 41° angle, to 1 decimal place.
Answer: 11.2 cm
- sin 41° = opposite ÷ hypotenuse
- opposite = 17 × sin 41°
- ≈ 11.2
2.In a right triangle, the side adjacent to a 38° angle is 13 m. Find the opposite side, to 1 decimal place.
Answer: 10.2 m
- tan 38° = opposite ÷ adjacent
- opposite = 13 × tan 38°
- ≈ 10.2
3.In a right triangle, the hypotenuse is 16 cm and one angle is 48°. Find the side opposite the 48° angle, to 1 decimal place.
Answer: 11.9 cm
- sin 48° = opposite ÷ hypotenuse
- opposite = 16 × sin 48°
- ≈ 11.9
4.In a right triangle, the side adjacent to a 33° angle is 12 m. Find the opposite side, to 1 decimal place.
Answer: 7.8 m
- tan 33° = opposite ÷ adjacent
- opposite = 12 × tan 33°
- ≈ 7.8
5.In a right triangle, the side adjacent to a 23° angle is 7 m. Find the opposite side, to 1 decimal place.
Answer: 3 m
- tan 23° = opposite ÷ adjacent
- opposite = 7 × tan 23°
- ≈ 3
6.In a right triangle, the hypotenuse is 25 cm and one angle is 57°. Find the side adjacent to the 57° angle, to 1 decimal place.
Answer: 13.6 cm
- cos 57° = adjacent ÷ hypotenuse
- adjacent = 25 × cos 57°
- ≈ 13.6
7.In a right triangle, the hypotenuse is 11 cm and one angle is 28°. Find the side opposite the 28° angle, to 1 decimal place.
Answer: 5.2 cm
- sin 28° = opposite ÷ hypotenuse
- opposite = 11 × sin 28°
- ≈ 5.2
8.In a right triangle, the hypotenuse is 22 cm and one angle is 22°. Find the side adjacent to the 22° angle, to 1 decimal place.
Answer: 20.4 cm
- cos 22° = adjacent ÷ hypotenuse
- adjacent = 22 × cos 22°
- ≈ 20.4
Marking tips
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