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Find a leg of a right triangle

Grade 8 math · Fieldbook Learning

Name ______________________ Date __________

Use a² + b² = c² and solve for the missing leg: subtract the known leg squared from the hypotenuse squared.

  1. A right triangle has a hypotenuse of 17 m and one leg of 8 m. How long is the other leg, in m?
  2. A right triangle has a hypotenuse of 41 m and one leg of 40 m. How long is the other leg, in m?
  3. A right triangle has a hypotenuse of 61 cm and one leg of 60 cm. How long is the other leg, in cm?
  4. A right triangle has a hypotenuse of 13 m and one leg of 12 m. How long is the other leg, in m?
  5. A right triangle has a hypotenuse of 26 km and one leg of 10 km. How long is the other leg, in km?
  6. A right triangle has a hypotenuse of 68 m and one leg of 60 m. How long is the other leg, in m?
  7. A right triangle has a hypotenuse of 123 km and one leg of 120 km. How long is the other leg, in km?
  8. A right triangle has a hypotenuse of 34 cm and one leg of 16 cm. How long is the other leg, in cm?
  9. A right triangle has a hypotenuse of 10 cm and one leg of 6 cm. How long is the other leg, in cm?
  10. A right triangle has a hypotenuse of 244 m and one leg of 240 m. How long is the other leg, in m?
  11. A right triangle has a hypotenuse of 20 m and one leg of 16 m. How long is the other leg, in m?
  12. A right triangle has a hypotenuse of 205 km and one leg of 200 km. How long is the other leg, in km?
  13. A right triangle has a hypotenuse of 122 m and one leg of 22 m. How long is the other leg, in m?
  14. A right triangle has a hypotenuse of 148 m and one leg of 140 m. How long is the other leg, in m?
  15. A right triangle has a hypotenuse of 150 m and one leg of 42 m. How long is the other leg, in m?
  16. A right triangle has a hypotenuse of 366 cm and one leg of 360 cm. How long is the other leg, in cm?
  17. A right triangle has a hypotenuse of 39 km and one leg of 15 km. How long is the other leg, in km?
  18. A right triangle has a hypotenuse of 17 km and one leg of 8 km. How long is the other leg, in km?
  19. A right triangle has a hypotenuse of 100 cm and one leg of 28 cm. How long is the other leg, in cm?
  20. A right triangle has a hypotenuse of 200 cm and one leg of 192 cm. How long is the other leg, in cm?
More free practice: fieldbooklearning.com/practice/grade-8/find-a-leg-of-a-right-triangle/

Play it as a quiz game

20 of these questions as multiple choice, with near-miss wrong answers, ready for Kahoot or Blooket.

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  2. Click the matching button below, then click the first empty question row of the template and paste.
  3. Save the template (Kahoot needs .xlsx, Blooket .csv) and upload it.
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Answer key: Find a leg of a right triangle

  1. 15
  2. 9
  3. 11
  4. 5
  5. 24
  6. 32
  7. 27
  8. 30
  9. 8
  10. 44
  11. 12
  12. 45
  13. 120
  14. 48
  15. 144
  16. 66
  17. 36
  18. 15
  19. 96
  20. 56