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9th Grade Trigonometry (Finding Sides) Worksheet — Level 3 — Practice Set 3 — 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 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 25 cm and one angle is 60°. Find the side adjacent to the 60° angle, to 1 decimal place.

Answer: 12.5 cm

  1. cos 60° = adjacent ÷ hypotenuse
  2. adjacent = 25 × cos 60°
  3. ≈ 12.5
2.In a right triangle, the side adjacent to a 56° angle is 8 m. Find the opposite side, to 1 decimal place.

Answer: 11.9 m

  1. tan 56° = opposite ÷ adjacent
  2. opposite = 8 × tan 56°
  3. ≈ 11.9
3.In a right triangle, the hypotenuse is 27 cm and one angle is 45°. Find the side adjacent to the 45° angle, to 1 decimal place.

Answer: 19.1 cm

  1. cos 45° = adjacent ÷ hypotenuse
  2. adjacent = 27 × cos 45°
  3. ≈ 19.1
4.In a right triangle, the hypotenuse is 21 cm and one angle is 21°. Find the side opposite the 21° angle, to 1 decimal place.

Answer: 7.5 cm

  1. sin 21° = opposite ÷ hypotenuse
  2. opposite = 21 × sin 21°
  3. ≈ 7.5
5.In a right triangle, the hypotenuse is 28 cm and one angle is 60°. Find the side adjacent to the 60° angle, to 1 decimal place.

Answer: 14 cm

  1. cos 60° = adjacent ÷ hypotenuse
  2. adjacent = 28 × cos 60°
  3. ≈ 14
6.In a right triangle, the hypotenuse is 13 cm and one angle is 50°. Find the side opposite the 50° angle, to 1 decimal place.

Answer: 10 cm

  1. sin 50° = opposite ÷ hypotenuse
  2. opposite = 13 × sin 50°
  3. ≈ 10
7.In a right triangle, the hypotenuse is 13 cm and one angle is 25°. Find the side adjacent to the 25° angle, to 1 decimal place.

Answer: 11.8 cm

  1. cos 25° = adjacent ÷ hypotenuse
  2. adjacent = 13 × cos 25°
  3. ≈ 11.8
8.In a right triangle, the hypotenuse is 10 cm and one angle is 29°. Find the side opposite the 29° angle, to 1 decimal place.

Answer: 4.8 cm

  1. sin 29° = opposite ÷ hypotenuse
  2. opposite = 10 × sin 29°
  3. ≈ 4.8
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