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Right-triangle trigonometry (SOHCAHTOA)

Apply sine, cosine and tangent ratios (SOHCAHTOA) in right-angled triangles and simplify to lowest terms. Review suitability for your learners before teaching.

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Worksheet StudioPractice pack · Ages 16-18

Right-triangle trigonometry (SOHCAHTOA)

Take your time. Show your thinking.

  1. 1. In a right-angled triangle, the side opposite angle θ is 8 cm, the adjacent side is 15 cm, and the hypotenuse is 17 cm. Write sin(θ) as a simplified fraction.

    Opp = 8, Adj = 15, Hyp = 17 · Right Triangle → sin(θ)
  2. 2. In a right-angled triangle, the side opposite angle θ is 64 cm, the adjacent side is 120 cm, and the hypotenuse is 136 cm. Write cos(θ) as a simplified fraction.

    Opp = 64, Adj = 120, Hyp = 136 · Right Triangle → cos(θ)
  3. 3. In a right-angled triangle, the side opposite angle θ is 24 cm, the adjacent side is 32 cm, and the hypotenuse is 40 cm. Write sin(θ) as a simplified fraction.

    Opp = 24, Adj = 32, Hyp = 40 · Right Triangle → sin(θ)
  4. 4. In a right-angled triangle, the side opposite angle θ is 14 cm, the adjacent side is 48 cm, and the hypotenuse is 50 cm. Write sin(θ) as a simplified fraction.

    Opp = 14, Adj = 48, Hyp = 50 · Right Triangle → sin(θ)
  5. 5. In a right-angled triangle, the side opposite angle θ is 48 cm, the adjacent side is 90 cm, and the hypotenuse is 102 cm. Write sin(θ) as a simplified fraction.

    Opp = 48, Adj = 90, Hyp = 102 · Right Triangle → sin(θ)
  6. 6. In a right-angled triangle, the side opposite angle θ is 7 cm, the adjacent side is 24 cm, and the hypotenuse is 25 cm. Write sin(θ) as a simplified fraction.

    Opp = 7, Adj = 24, Hyp = 25 · Right Triangle → sin(θ)
  7. 7. In a right-angled triangle, the side opposite angle θ is 3 cm, the adjacent side is 4 cm, and the hypotenuse is 5 cm. Write sin(θ) as a simplified fraction.

    Opp = 3, Adj = 4, Hyp = 5 · Right Triangle → sin(θ)
  8. 8. In a right-angled triangle, the side opposite angle θ is 10 cm, the adjacent side is 24 cm, and the hypotenuse is 26 cm. Write sin(θ) as a simplified fraction.

    Opp = 10, Adj = 24, Hyp = 26 · Right Triangle → sin(θ)
  9. 9. In a right-angled triangle, the side opposite angle θ is 24 cm, the adjacent side is 32 cm, and the hypotenuse is 40 cm. Write tan(θ) as a simplified fraction.

    Opp = 24, Adj = 32, Hyp = 40 · Right Triangle → tan(θ)
  10. 10. In a right-angled triangle, the side opposite angle θ is 40 cm, the adjacent side is 75 cm, and the hypotenuse is 85 cm. Write cos(θ) as a simplified fraction.

    Opp = 40, Adj = 75, Hyp = 85 · Right Triangle → cos(θ)
  11. 11. In a right-angled triangle, the side opposite angle θ is 40 cm, the adjacent side is 75 cm, and the hypotenuse is 85 cm. Write tan(θ) as a simplified fraction.

    Opp = 40, Adj = 75, Hyp = 85 · Right Triangle → tan(θ)
  12. 12. In a right-angled triangle, the side opposite angle θ is 35 cm, the adjacent side is 120 cm, and the hypotenuse is 125 cm. Write sin(θ) as a simplified fraction.

    Opp = 35, Adj = 120, Hyp = 125 · Right Triangle → sin(θ)
12 questions · Seed 58 · Age guidance, not curriculum certification
View the answer key
Worksheet StudioAnswer key · Ages 16-18

Right-triangle trigonometry (SOHCAHTOA)

Answers and reasoning. Review before teaching.

  1. 1. In a right-angled triangle, the side opposite angle θ is 8 cm, the adjacent side is 15 cm, and the hypotenuse is 17 cm. Write sin(θ) as a simplified fraction.

    8/17

    sin(θ) = opposite ÷ hypotenuse = 8/17, which simplifies by dividing by 1 to 8/17.

  2. 2. In a right-angled triangle, the side opposite angle θ is 64 cm, the adjacent side is 120 cm, and the hypotenuse is 136 cm. Write cos(θ) as a simplified fraction.

    15/17

    cos(θ) = adjacent ÷ hypotenuse = 120/136, which simplifies by dividing by 8 to 15/17.

  3. 3. In a right-angled triangle, the side opposite angle θ is 24 cm, the adjacent side is 32 cm, and the hypotenuse is 40 cm. Write sin(θ) as a simplified fraction.

    3/5

    sin(θ) = opposite ÷ hypotenuse = 24/40, which simplifies by dividing by 8 to 3/5.

  4. 4. In a right-angled triangle, the side opposite angle θ is 14 cm, the adjacent side is 48 cm, and the hypotenuse is 50 cm. Write sin(θ) as a simplified fraction.

    7/25

    sin(θ) = opposite ÷ hypotenuse = 14/50, which simplifies by dividing by 2 to 7/25.

  5. 5. In a right-angled triangle, the side opposite angle θ is 48 cm, the adjacent side is 90 cm, and the hypotenuse is 102 cm. Write sin(θ) as a simplified fraction.

    8/17

    sin(θ) = opposite ÷ hypotenuse = 48/102, which simplifies by dividing by 6 to 8/17.

  6. 6. In a right-angled triangle, the side opposite angle θ is 7 cm, the adjacent side is 24 cm, and the hypotenuse is 25 cm. Write sin(θ) as a simplified fraction.

    7/25

    sin(θ) = opposite ÷ hypotenuse = 7/25, which simplifies by dividing by 1 to 7/25.

  7. 7. In a right-angled triangle, the side opposite angle θ is 3 cm, the adjacent side is 4 cm, and the hypotenuse is 5 cm. Write sin(θ) as a simplified fraction.

    3/5

    sin(θ) = opposite ÷ hypotenuse = 3/5, which simplifies by dividing by 1 to 3/5.

  8. 8. In a right-angled triangle, the side opposite angle θ is 10 cm, the adjacent side is 24 cm, and the hypotenuse is 26 cm. Write sin(θ) as a simplified fraction.

    5/13

    sin(θ) = opposite ÷ hypotenuse = 10/26, which simplifies by dividing by 2 to 5/13.

  9. 9. In a right-angled triangle, the side opposite angle θ is 24 cm, the adjacent side is 32 cm, and the hypotenuse is 40 cm. Write tan(θ) as a simplified fraction.

    3/4

    tan(θ) = opposite ÷ adjacent = 24/32, which simplifies by dividing by 8 to 3/4.

  10. 10. In a right-angled triangle, the side opposite angle θ is 40 cm, the adjacent side is 75 cm, and the hypotenuse is 85 cm. Write cos(θ) as a simplified fraction.

    15/17

    cos(θ) = adjacent ÷ hypotenuse = 75/85, which simplifies by dividing by 5 to 15/17.

  11. 11. In a right-angled triangle, the side opposite angle θ is 40 cm, the adjacent side is 75 cm, and the hypotenuse is 85 cm. Write tan(θ) as a simplified fraction.

    8/15

    tan(θ) = opposite ÷ adjacent = 40/75, which simplifies by dividing by 5 to 8/15.

  12. 12. In a right-angled triangle, the side opposite angle θ is 35 cm, the adjacent side is 120 cm, and the hypotenuse is 125 cm. Write sin(θ) as a simplified fraction.

    7/25

    sin(θ) = opposite ÷ hypotenuse = 35/125, which simplifies by dividing by 5 to 7/25.

12 questions · Seed 58 · Age guidance, not curriculum certification