NCERT Ganita Prakash, Class 8, textbook pages 148–176 (Part 2)

How to teach Class 8 Maths Part 2 Chapter 7, Area, at home

Area of rectangles, parallelograms, triangles, trapeziums, 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.

abharea = ½ (a + b) × h

NCERT Class 8 Maths Part 2 Chapter 7 Area: what it teaches

Your child divides and rearranges shapes to find area formulas: parallelogram = base × height, triangle = ½ × base × height, trapezium = ½ × (sum of parallel sides) × height, and areas of rhombuses and composite shapes.

Why it matters later. Area formulas lead to surface area and volume in Classes 9–10.

See it: this chapter in pictures

parallelogram: base × height
Height is perpendicular to the base.
triangle: base 10, height 6½ × 10 × 6= 30
Half of a parallelogram.
split into two rectangles
Split composite shapes into simple ones.

You need

  • squared paper
  • scissors
  • a ruler

Tonight’s 30 minutes

  1. Cut a parallelogram, move the triangle to make a rectangle. Area = base × height.
  2. Two identical triangles make a parallelogram: triangle area = ½ bh.
  3. Two identical trapeziums make a parallelogram: find the trapezium formula.
  4. Find the area of an L-shaped room by splitting it.

Words to use

  • area
  • base
  • height
  • parallelogram
  • trapezium
  • composite shape

Watch for

  • Using the slant side as height. Height is perpendicular to the base.
  • Forgetting ½ for triangles. Draw the rectangle around it to see the half.

What it sounds like at home

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

YouParallel sides 6 and 10, height 4. Area?

Your child½ × 16 × 4 = 32.

A game for this week: Area designer

  1. Draw a composite shape on squared paper.
  2. The other player finds the area by splitting.
  3. Check by counting squares.
  4. Swap roles.

A 5-day plan, 30 minutes a day

  1. Day 1Parallelogram cut-and-move.
  2. Day 2Triangle as half.
  3. Day 3Trapezium formula.
  4. Day 4Composite shapes.
  5. Day 5Area designer.

Everyday moments to practise

  • Plots of land.
  • Tiling floors.
  • Painting walls.
  • Garden design.

Quick check

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

Area of a parallelogram with base 8, height 5?

40.

Triangle base 10, height 6?

30.

Trapezium with parallel sides 6 and 10, height 4?

32.

Ready for the next chapter when your child…

  • Uses area formulas.
  • Identifies the correct height.
  • Finds areas of composite shapes.

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

How is the trapezium formula found?

Two trapeziums make a parallelogram with base (a + b).

What is the height of a parallelogram?

The perpendicular distance between the base and the opposite side.

How do I find the area of odd shapes?

Split into rectangles, triangles and trapeziums.