NCERT Solutions for Class 8 Maths Chapter 3 – Understanding Quadrilaterals Chapter 3 describes the plane curves like various types of polygons as a triangle, quadrilateral, pentagon, hexagon, heptagon, etc. Exercise 3.1 briefs about the interior and exterior parts of a closed figure, diagonals of a polygon, convex and concave polygons, and angle sum property of a polygon. NCERT Solutions of class 9 math contains all chapter solutions in pdf. Solutions can be downloaded chapter wise. NCERT solutions for class 9 covers all the chapters including Area of Parallelograms and Triangles, Circle, Constructions, Heron’s Formula, Introduction to euclid’s geometry, Lines and Angles, Number System, Polynomials ...