Concise Selina Solutions for Class 8 maths Chapter 16 Understanding Shapes

In geometry, a shape can be defined as the form of an object or its outline, outer boundary or outer surface. Everything we see in the world around us has a shape. Understanding shapes explains about properties of quadrilaterals, angle sum property, properties of parallelograms, kinds of quadrilaterals and theorems related to them. Knowing this chapter is important because it has applications in everyday life, e.g., thinking about home projects, and in various careers, like architecture. Thus, a plane figure bounded by four line segments AB, BC, CD and DA is called a quadrilateral and is written as quad ABCD. A quadrilateral has four sides, four angles, four vertices and two diagonals. Quadrilaterals can be classified into different types based on their sides and angles. Shapes are of two kinds: plane shapes and solid shapes. Plane shapes are triangle, circle etc.