Class 8 Maths Part 1 Chapter 4, Quadrilaterals, begins with a carpenter’s problem—how to build a rectangular frame using diagonal strips—and uses geometry and congruence to deduce the properties of rectangles, squares, parallelograms, rhombuses, kites and trapeziums.
What Class 8 Maths Chapter 4 Covers
4.1 Rectangles and Squares and 4.2 Angles in a Quadrilateral use triangle congruence on diagonals to prove why rectangle diagonals are equal and bisect each other, why square diagonals meet at 90°, and why the angles of any quadrilateral sum to 360°.
4.3 Parallelograms and 4.4 Rhombuses generalise to quadrilaterals with parallel opposite sides (parallelograms) and equal sidelengths (rhombuses), mapping their hierarchy with a Venn diagram.
4.5 Playing with Quadrilaterals and 4.6 Kite and Trapezium use geoboards, triangle joining and paper-folding (‘Which Quad?’) to study kites and trapeziums.
Exercises in Chapter 4
- Figure it Out exercise sets after each major section, with complete answer keys at the end of the chapter.
Read Class 8 Maths Chapter 4 Online
More Chapters
- Previous: Chapter 3: A Story of Numbers
- Next: Chapter 5: Number Play
- Hindi medium: Class 8 Maths Part 1 Chapter 4 PDF in Hindi (Ganita Prakash)
- All Maths chapters and the other Class 8 books: Class 8 NCERT books 2026-27
- All Class 1 to 12 NCERT Textbooks: NCERT Books PDF (Class 1–12)
- Every book chapter by chapter: NCERT chapter wise PDF
FAQ
What is the sum of interior angles of a quadrilateral?
360°, because any quadrilateral can be divided by a diagonal into two triangles whose angles each sum to 180°.
How do the diagonals of a rectangle and a rhombus differ?
A rectangle’s diagonals are equal in length and bisect each other; a rhombus’s diagonals bisect each other at right angles (90°) and bisect the vertex angles.