Download Quadrilaterals – NCERT Class 8 Maths Chapter 4 PDF from the new NCERT Class 8 Maths book Ganita Prakash (2026-27). Read the chapter online or download the free PDF. A rectangle can be defined in three equivalent ways — all angles 90°; all angles 90° with opposite sides equal; or diagonals equal and bisecting each other. The chapter proves that these describe exactly the same set of quadrilaterals.
Quadrilaterals PDF – Chapter 4 of Ganita Prakash (Part I)
Read the chapter online or download the PDF.
| Chapter | Download | |
|---|---|---|
| Chapter 4 PDF | Quadrilaterals | View PDF |
| Full book | NCERT Class 8 Maths – Ganita Prakash | View Book |
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What Is in Quadrilaterals? (Class 8 Maths Chapter 4)
- A rectangle can be defined in three equivalent ways — all angles 90°; all angles 90° with opposite sides equal; or diagonals equal and bisecting each other. The chapter proves that these describe exactly the same set of quadrilaterals.
- Congruence does the heavy lifting. SAS, AAS, ASA and SSS are used in Deductions 1–10 to establish every side, angle and diagonal property in the chapter.
- The angle sum of any quadrilateral is 360°, because one diagonal splits it into two triangles. This is why three right angles force the fourth to be a right angle too.
- Parallelogram: opposite sides parallel ⇒ opposite sides equal, opposite angles equal, adjacent angles supplementary, diagonals bisect each other. A rhombus adds equal sides; the diagonals then also become perpendicular and bisect the angles.
- Venn diagrams keep the family straight: every square is a rectangle, a rhombus, a parallelogram and a kite; every rectangle and every rhombus is a parallelogram; a parallelogram need not be any of these.
- A kite has two adjacent pairs of equal sides; a trapezium needs at least one pair of parallel sides. In an isosceles trapezium the angles on each parallel side are equal.
Quick revision – Quadrilaterals
| Quadrilateral | Definition used in the book | Sides and angles | Diagonals |
|---|---|---|---|
| Rectangle | All four angles are 90° | Opposite sides equal and parallel | Equal; bisect each other |
| Square | All angles 90° and all sides equal | All sides equal, opposite sides parallel | Equal; bisect each other at 90°; bisect the angles |
| Parallelogram | Opposite sides are parallel | Opposite sides equal; opposite angles equal; adjacent angles add to 180° | Bisect each other (need not be equal) |
| Rhombus | All four sides are equal | Opposite sides parallel; opposite angles equal; adjacent angles add to 180° | Bisect each other at 90°; bisect the angles (need not be equal) |
| Kite | Can be labelled ABCD with AB = BC and CD = DA | Two adjacent pairs of equal sides; one pair of opposite angles equal | One diagonal bisects the other at 90° and bisects two angles |
| Trapezium | At least one pair of parallel opposite sides | Angles on the same leg add to 180° | No special property |
| Isosceles trapezium | Trapezium whose non-parallel sides are equal | Angles on each parallel side are equal | Equal in length |
| Any quadrilateral | Closed figure with four sides | Angle sum is 360° | A diagonal splits it into two triangles |
Old NCERT vs New – Class 8 Maths
This chapter is from Ganita Prakash, the new NCERT Class 8 Maths book (NCF-SE 2023, used from 2025-26). It replaced the old book “Mathematics”, so chapter numbers and names differ from older PDFs.
Solutions and All Chapters
Answers to the exercises and the full chapter list of Ganita Prakash:
Quadrilaterals – Overview
| Class | Class 8 |
| Subject | Maths |
| Book | Ganita Prakash – new NCERT book |
| Part | Part I |
| Chapter | 4 of 14 – Quadrilaterals |
| Book pages | 82 – 111 |
| Edition | NCERT Reprint 2026-27 |
| Session | 2026-27 |
| Free – read online or download |
Class 8 Maths Chapter 4 – FAQs
Where can I download Quadrilaterals Class 8 PDF?
From the download table on this page – the chapter PDF is free, and the full book is linked too.
What is Class 8 Maths Chapter 4 about?
A rectangle can be defined in three equivalent ways — all angles 90°; all angles 90° with opposite sides equal; or diagonals equal and bisecting each other. The chapter proves that these describe exactly the same set of quadrilaterals.
Is Quadrilaterals from the new NCERT Class 8 Maths book?
Yes. It is chapter 4 of ganita prakash (part i), the new NCERT Class 8 Maths book for 2026-27.
Is this the latest NCERT edition for 2026-27?
Yes – the PDF is NCERT’s latest edition for the 2026-27 session.
Where are the NCERT Solutions for Class 8 Maths Chapter 4?
Open the NCERT Solutions link above for answers to the exercise questions.