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9th Grade Trigonometry (Finding Sides) Worksheet — Level 1 — Practice Set 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 1 — Practice Set 2 — Answers

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

1.In a right triangle, the hypotenuse is 10 cm and one angle is 47°. Find the side opposite the 47° angle, to 1 decimal place.

Answer: 7.3 cm

  1. sin 47° = opposite ÷ hypotenuse
  2. opposite = 10 × sin 47°
  3. ≈ 7.3
2.In a right triangle, the hypotenuse is 28 cm and one angle is 42°. Find the side opposite the 42° angle, to 1 decimal place.

Answer: 18.7 cm

  1. sin 42° = opposite ÷ hypotenuse
  2. opposite = 28 × sin 42°
  3. ≈ 18.7
3.In a right triangle, the hypotenuse is 28 cm and one angle is 23°. Find the side opposite the 23° angle, to 1 decimal place.

Answer: 10.9 cm

  1. sin 23° = opposite ÷ hypotenuse
  2. opposite = 28 × sin 23°
  3. ≈ 10.9
4.In a right triangle, the hypotenuse is 25 cm and one angle is 20°. Find the side opposite the 20° angle, to 1 decimal place.

Answer: 8.6 cm

  1. sin 20° = opposite ÷ hypotenuse
  2. opposite = 25 × sin 20°
  3. ≈ 8.6
5.In a right triangle, the hypotenuse is 21 cm and one angle is 51°. Find the side opposite the 51° angle, to 1 decimal place.

Answer: 16.3 cm

  1. sin 51° = opposite ÷ hypotenuse
  2. opposite = 21 × sin 51°
  3. ≈ 16.3
6.In a right triangle, the hypotenuse is 6 cm and one angle is 35°. Find the side opposite the 35° angle, to 1 decimal place.

Answer: 3.4 cm

  1. sin 35° = opposite ÷ hypotenuse
  2. opposite = 6 × sin 35°
  3. ≈ 3.4
7.In a right triangle, the hypotenuse is 6 cm and one angle is 57°. Find the side opposite the 57° angle, to 1 decimal place.

Answer: 5 cm

  1. sin 57° = opposite ÷ hypotenuse
  2. opposite = 6 × sin 57°
  3. ≈ 5
8.In a right triangle, the hypotenuse is 21 cm and one angle is 49°. Find the side opposite the 49° angle, to 1 decimal place.

Answer: 15.8 cm

  1. sin 49° = opposite ÷ hypotenuse
  2. opposite = 21 × sin 49°
  3. ≈ 15.8
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