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

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

1.In a right triangle, the hypotenuse is 30 cm and one angle is 38°. Find the side opposite the 38° angle, to 1 decimal place.

Answer: 18.5 cm

  1. sin 38° = opposite ÷ hypotenuse
  2. opposite = 30 × sin 38°
  3. ≈ 18.5
2.In a right triangle, the hypotenuse is 13 cm and one angle is 39°. Find the side opposite the 39° angle, to 1 decimal place.

Answer: 8.2 cm

  1. sin 39° = opposite ÷ hypotenuse
  2. opposite = 13 × sin 39°
  3. ≈ 8.2
3.In a right triangle, the hypotenuse is 26 cm and one angle is 26°. Find the side opposite the 26° angle, to 1 decimal place.

Answer: 11.4 cm

  1. sin 26° = opposite ÷ hypotenuse
  2. opposite = 26 × sin 26°
  3. ≈ 11.4
4.In a right triangle, the hypotenuse is 25 cm and one angle is 40°. Find the side opposite the 40° angle, to 1 decimal place.

Answer: 16.1 cm

  1. sin 40° = opposite ÷ hypotenuse
  2. opposite = 25 × sin 40°
  3. ≈ 16.1
5.In a right triangle, the hypotenuse is 19 cm and one angle is 51°. Find the side opposite the 51° angle, to 1 decimal place.

Answer: 14.8 cm

  1. sin 51° = opposite ÷ hypotenuse
  2. opposite = 19 × sin 51°
  3. ≈ 14.8
6.In a right triangle, the hypotenuse is 14 cm and one angle is 59°. Find the side opposite the 59° angle, to 1 decimal place.

Answer: 12 cm

  1. sin 59° = opposite ÷ hypotenuse
  2. opposite = 14 × sin 59°
  3. ≈ 12
7.In a right triangle, the hypotenuse is 21 cm and one angle is 56°. Find the side opposite the 56° angle, to 1 decimal place.

Answer: 17.4 cm

  1. sin 56° = opposite ÷ hypotenuse
  2. opposite = 21 × sin 56°
  3. ≈ 17.4
8.In a right triangle, the hypotenuse is 9 cm and one angle is 47°. Find the side opposite the 47° angle, to 1 decimal place.

Answer: 6.6 cm

  1. sin 47° = opposite ÷ hypotenuse
  2. opposite = 9 × sin 47°
  3. ≈ 6.6
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