NCERT Solutions for Class 8 Maths Chapter 3 – Understanding Quadrilaterals

NCERT Solutions for Class 8 Maths Chapter 3 ‘Understanding Quadrilaterals’ deal with all the essential topics of the chapter. This particular chapter of NCERT Solutions Class 8 Maths textbook discusses the quadrilaterals in an in-depth manner and so does it provides an insight into the types of quadrilaterals such as square, kite, trapezium and rhombus amongst others. There are 4 exercises and a total of 33 questions in this chapter.

While studying this chapter you might get confused with the properties of rectangle and parallelogram as most of them are similar. You must also have a clear understanding of the exterior angle property and angle sum property of polygons to solve the questions of this chapter. By solving the NCERT exercises you will learn how to find the angles of different polygons such as parallelograms, trapeziums, rectangles etc.  To make the fundamentals of this chapter stronger, you can refer to the CBSE NCERT Solutions by Instasolv as and when required.

Mathematics can undoubtedly become a difficult subject to tackle in Class 8 if you are not sure about your basic concepts and formulas. Keeping this in mind, the subject matter experts at Instasolv have drafted NCERT Solutions for Class 8 Chapter 3- Understanding Quadrilaterals in the simplest yet comprehensive manner to guide you better. It is highly advised that you add these solutions to your study routine for this chapter.

Overview of NCERT Solutions for Class 8 Maths Chapter 3- Understanding Quadrilaterals

If you want to score good marks during the CBSE exam, then understanding Chapter 3 of NCERT Solutions for Class 8 is extremely essential for you. This chapter covers the concepts of curves, polygons, quadrilaterals and also parallelograms. The definitions and essential properties of each of these figures have been covered elaborately in this chapter. 

Important Concepts to remember from Chapter 3- Understanding Quadrilaterals

Let us quickly discuss all the important concepts of NCERT Maths Chapter 3 Understanding Quadrilaterals.

Curves: In the simple terms a Curve is a figure that is created by joining two points on a surface without lifting the pencil/pen. There are two types of curves: Open Curves and Closed Curves. 

Polygons: These are the types of closed curves which consist of the line segments. Polygons are classified according to the number of sides. For instance, the polygons having 3 sides are called Triangles and the polygon having 6 sides is Hexagon and so forth. 

Angles of Polygons

The sum of the interior angles of a polygon is (n-2)* 180. In this formula, ‘n’ stands for the number of sides of the polygon. For example, the sum of interior angles of a quadrilateral (i.e. a polygon with 4 sides) will be (4-2)* 180 = 360 degrees.

On the other hand, the sum of the exterior angles of a polygon is 360 degrees and it remains the same for all kinds of polygons. 


These are the closed polygons having four sides, four angles and four vertices. Quadrilaterals are of the following types:

  • Trapezium having one pair of sides which are parallel.
  • Kite having two pair of adjacent sides which are equal i.e. AB=BC and AD=CD in a kite.
  • Parallelogram having two pairs of opposite sides which are parallel to each other.


Parallelograms are figures which have equal opposite sides. Properties of the parallelogram which help solve the important mathematic questions include:

In a parallelogram ABCD, 

~AB=DC and AD=BC

~ A =C and D =B

~Sum of the two Adjacent angles of a parallelogram is 180 degrees i.e.

A+B= 180, B+ C= 180, C+D=180 and D+A= 180.

Types of parallelograms are: 

  • Square having all four equal sides and four angles which are 90 degrees each.
  • Rectangle having equal opposite sides and four angles which are 90 degrees each.
  • Rhombus having all four equal sides but the point of intersection of the diagonals make an angle of 90 degrees. 

Exercise-wise Discussion of NCERT Class 8 Maths Chapter 3 

Questions related to quadrilaterals form the core of class 8 CBSE maths syllabus. So the 4 exercises at the end of Chapter 3- Understanding Quadrilaterals are enough to help you test your knowledge in the best possible manner.

Exercise 3.1 helps you identify and classify different polygons, diagonals of different diagrams and you get an idea of how to solve questions to find angles of given quadrilaterals. Exercise 3.2 deals with more questions on exterior angles of quadrilaterals and has around 6 questions. 

The longest exercise is Exercise 3.3 of this chapter having 12 questions out of which most are related to parallelograms and trapezium. Properties of different quadrilaterals have been covered in Exercise 3.4 of the chapter ensuring that you end the lesson with complete and fruitful knowledge. 

Importance of NCERT Solutions for Class 8 Maths Chapter 3- Understanding Quadrilaterals by Instasolv

  • We provide accurately devised and CBSE syllabus oriented NCERT Solutions for Class 8 Maths Chapter 3-Understanding Quadrilaterals 
  • Along with the NCERT solutions, quick revision notes are also available to help you revise the significant points especially before your maths exam
  • Whether it is Choosing the Correct Figure, One-Word Answers or Angles to be found by solving questions- all types of questions are covered in details in our NCERT solutions
  • As you know that maths needs to be practised, so these solutions help you get into the habit of practising as many questions as possible 
  • With the help of our CBSE class 8 maths chapter 3 solutions, you will also learn to solve Maths questions with great speed and precision

Quick Tips for Preparing Chapter 3- Understanding Quadrilaterals

  • Read the NCERT chapter at least twice or thrice to know what it entails and what kind of preparation is required for that chapter.
  • Since there are many concepts which are defined in this chapter, it is advised that you keep a notebook and jot down all important points to remember for your reference.
  • Anytime you get stuck in solving any of the questions, refer to the NCERT Solutions offered by Instasolv to answer your questions perfectly.