Chapter 6 · Question 6

State Pythagoras theorem and its converse.

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Q6

State Pythagoras theorem and its converse.

Answer Revealed
Direct Answer:
In a right triangle, the square of the hypotenuse equals the sum of the squares of the other two sides: c2=a2+b2c^2=a^2+b^2. Conversely, if one side square equals the sum of squares of the other two sides, the triangle is right-angled.

Simple Explanation

Right triangle formula: hypotenuse squared equals sum of other two squares.

Exam-Ready Structure

If ABC\triangle ABC is right-angled at BB, then AC2=AB2+BC2AC^2=AB^2+BC^2. Conversely, if in a triangle AC2=AB2+BC2AC^2=AB^2+BC^2, then the angle opposite ACAC is a right angle. NCERT uses similarity of triangles to prove this result.

Key Points

  • In a right triangle, the square of the hypotenuse equals the sum of the squares of the other two sides: c2=a2+b2c^2=a^2+b^2.
  • Use the NCERT formula or theorem carefully.
  • Write units and final conclusion where applicable.