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Year 11 Trigonometry (Finding Sides) Worksheet — Level 1 — Answers

Answer sheet with worked solutions for the Year 11 trigonometry worksheet.

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Success TutoringWorksheetsAnswer sheetYear 11 · Mathematics · Trigonometry

Year 11 Trigonometry (Finding Sides) Worksheet — Level 1 — Answers

Label the sides (opposite, adjacent, hypotenuse), choose the ratio (SOH CAH TOA), then solve.

1.In a right-angled triangle, the hypotenuse is 28 cm and one angle is 26°. Find the side opposite the 26° angle, to 1 decimal place.

Answer: 12.3 cm

  1. sin 26° = opposite ÷ hypotenuse
  2. opposite = 28 × sin 26°
  3. ≈ 12.3
2.In a right-angled triangle, the hypotenuse is 19 cm and one angle is 50°. Find the side opposite the 50° angle, to 1 decimal place.

Answer: 14.6 cm

  1. sin 50° = opposite ÷ hypotenuse
  2. opposite = 19 × sin 50°
  3. ≈ 14.6
3.In a right-angled triangle, the hypotenuse is 28 cm and one angle is 70°. Find the side opposite the 70° angle, to 1 decimal place.

Answer: 26.3 cm

  1. sin 70° = opposite ÷ hypotenuse
  2. opposite = 28 × sin 70°
  3. ≈ 26.3
4.In a right-angled triangle, the hypotenuse is 27 cm and one angle is 22°. Find the side opposite the 22° angle, to 1 decimal place.

Answer: 10.1 cm

  1. sin 22° = opposite ÷ hypotenuse
  2. opposite = 27 × sin 22°
  3. ≈ 10.1
5.In a right-angled triangle, the hypotenuse is 10 cm and one angle is 66°. Find the side opposite the 66° angle, to 1 decimal place.

Answer: 9.1 cm

  1. sin 66° = opposite ÷ hypotenuse
  2. opposite = 10 × sin 66°
  3. ≈ 9.1
6.In a right-angled triangle, the hypotenuse is 8 cm and one angle is 23°. Find the side opposite the 23° angle, to 1 decimal place.

Answer: 3.1 cm

  1. sin 23° = opposite ÷ hypotenuse
  2. opposite = 8 × sin 23°
  3. ≈ 3.1
7.In a right-angled triangle, the hypotenuse is 30 cm and one angle is 55°. Find the side opposite the 55° angle, to 1 decimal place.

Answer: 24.6 cm

  1. sin 55° = opposite ÷ hypotenuse
  2. opposite = 30 × sin 55°
  3. ≈ 24.6
8.In a right-angled triangle, the hypotenuse is 27 cm and one angle is 43°. Find the side opposite the 43° angle, to 1 decimal place.

Answer: 18.4 cm

  1. sin 43° = opposite ÷ hypotenuse
  2. opposite = 27 × sin 43°
  3. ≈ 18.4
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