NCERT Ganita Prakash, Class 8, textbook pages 33–54 (Part 2)

How to teach Class 8 Maths Part 2 Chapter 2, The Baudhayana-Pythagoras Theorem, at home

Right triangles and a² + b² = c², taught with things you already have at home: a 30-minute activity, a game for the week, a 5-day plan and the mistakes to watch for.

4353² + 4²= 9 + 16= 25 = 5²

NCERT Class 8 Maths Part 2 Chapter 2 The Baudhayana-Pythagoras Theorem: what it teaches

Baudhayana described this around 800 BCE: in a right triangle, the square on the longest side equals the sum of squares on the other two. Your child sees it with squares on sides, finds missing sides and checks for right angles.

Why it matters later. The theorem is used in coordinate geometry, trigonometry and physics.

See it: this chapter in pictures

legs 6 and 86² + 8² = 100hypotenuse = 10
Square, add, take the root.
3, 4, 55, 12, 138, 15, 17
Whole-number right triangles.
3 m + 4 m along wallscorners 5 m apart?yes → square corner
The converse checks right angles.

You need

  • squared paper
  • scissors
  • a measuring tape

Tonight’s 30 minutes

  1. Draw a right triangle 3 by 4 on squared paper. Measure the hypotenuse (5).
  2. Draw squares on each side and count: 9 + 16 = 25.
  3. Find the diagonal of a 6 × 8 rectangle (10).
  4. Check if a room corner is square: 3 m and 4 m along walls should be 5 m apart.

Words to use

  • hypotenuse
  • right triangle
  • square
  • Pythagorean triple
  • converse

Watch for

  • Using the theorem for non-right triangles. It only works when there is a right angle.
  • Adding sides instead of squares. Square first, add, then take the square root.

What it sounds like at home

A short example of the conversation. Your words will differ; the questions are what matter.

YouLegs 6 and 8. Hypotenuse?

Your child36 + 64 = 100, so 10.

A game for this week: Triple hunter

  1. Find whole-number triples (3,4,5; 5,12,13…).
  2. Check each with squares.
  3. Scale triples: 6, 8, 10.
  4. Most triples wins.

A 5-day plan, 30 minutes a day

  1. Day 13-4-5 on squared paper.
  2. Day 2Squares on sides.
  3. Day 3Rectangle diagonals.
  4. Day 4Checking square corners.
  5. Day 5Triple hunter.

Everyday moments to practise

  • Ladder against a wall.
  • TV screen sizes (diagonal).
  • Building corners.
  • Shortest path across a field.

Quick check

Ask these at the end of the week. Tap to see the answer.

Hypotenuse of legs 6 and 8?

10.

Is 5, 12, 13 a right triangle?

Yes: 25 + 144 = 169.

Leg if hypotenuse 13 and other leg 5?

12.

Ready for the next chapter when your child…

  • States and uses the theorem.
  • Finds missing sides.
  • Checks right angles with the converse.

Activities, wording and illustrations are Mathify Kids’ own, following the topics of NCERT’s Ganita Prakash (Class 8). See the full Class 8 parent guide for every chapter.

Questions parents ask

Who discovered the theorem?

It appears in Baudhayana’s Sulba Sutras around 800 BCE, before Pythagoras.

What is a Pythagorean triple?

Whole numbers a, b, c with a² + b² = c².

How do builders use it?

The 3-4-5 rule checks square corners.