16Hit1600
Geometry and TrigonometryEasy–MediumPythagorean theorem

Geometry and Trigonometry practice question

A right triangle has legs of length 6 and 8. What is the length of the hypotenuse?

  1. A. 10Correct
  2. B. 12
  3. C. 14
  4. D. 48

Answer: A. 10

Hypotenuse² = 6² + 8² = 36 + 64 = 100, so the hypotenuse = 10. This is the famous 3-4-5 triangle scaled by 2.

Why the other answers are wrong

B. 12
12 doesn't come from any step of the Pythagorean theorem — it's a decoy. Compute 6² + 8² = 100 and take the square root to get 10.
C. 14
14 is 6 + 8; the legs add only after you square them: √(36 + 64) = 10.
D. 48
48 is 6 × 8, the product of the legs. The Pythagorean theorem squares each leg, adds, then takes the square root.

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