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9th Grade Trigonometry (Finding Sides) Worksheet — Level 2 — Answers

Answer sheet with worked solutions for the 9th Grade trigonometry worksheet.

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Success TutoringWorksheetsAnswer sheet9th Grade · Mathematics · Trigonometry

9th Grade Trigonometry (Finding Sides) Worksheet — Level 2 — Answers

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

1.In a right triangle, the hypotenuse is 8 cm and one angle is 56°. Find the side opposite the 56° angle, to 1 decimal place.

Answer: 6.6 cm

  1. sin 56° = opposite ÷ hypotenuse
  2. opposite = 8 × sin 56°
  3. ≈ 6.6
2.In a right triangle, the hypotenuse is 29 cm and one angle is 70°. Find the side opposite the 70° angle, to 1 decimal place.

Answer: 27.3 cm

  1. sin 70° = opposite ÷ hypotenuse
  2. opposite = 29 × sin 70°
  3. ≈ 27.3
3.In a right triangle, the hypotenuse is 21 cm and one angle is 60°. Find the side adjacent to the 60° angle, to 1 decimal place.

Answer: 10.5 cm

  1. cos 60° = adjacent ÷ hypotenuse
  2. adjacent = 21 × cos 60°
  3. ≈ 10.5
4.In a right triangle, the hypotenuse is 7 cm and one angle is 31°. Find the side adjacent to the 31° angle, to 1 decimal place.

Answer: 6 cm

  1. cos 31° = adjacent ÷ hypotenuse
  2. adjacent = 7 × cos 31°
  3. ≈ 6
5.In a right triangle, the side adjacent to a 30° angle is 13 m. Find the opposite side, to 1 decimal place.

Answer: 7.5 m

  1. tan 30° = opposite ÷ adjacent
  2. opposite = 13 × tan 30°
  3. ≈ 7.5
6.In a right triangle, the side adjacent to a 31° angle is 6 m. Find the opposite side, to 1 decimal place.

Answer: 3.6 m

  1. tan 31° = opposite ÷ adjacent
  2. opposite = 6 × tan 31°
  3. ≈ 3.6
7.In a right triangle, the hypotenuse is 15 cm and one angle is 66°. Find the side adjacent to the 66° angle, to 1 decimal place.

Answer: 6.1 cm

  1. cos 66° = adjacent ÷ hypotenuse
  2. adjacent = 15 × cos 66°
  3. ≈ 6.1
8.In a right triangle, the hypotenuse is 27 cm and one angle is 36°. Find the side adjacent to the 36° angle, to 1 decimal place.

Answer: 21.8 cm

  1. cos 36° = adjacent ÷ hypotenuse
  2. adjacent = 27 × cos 36°
  3. ≈ 21.8
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