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SAI International School
                                                      Grade -VII
               Mathematics

               CHAPTER-15: VISUALISING SOLID SHAPES
               Lesson Note-1


               SUBTOPICS: PLANE FIGURES, SOLID FIGURES, FACES, EDGES, VERTICES

                    Introduction: Plane Figures And Solid Shapes
                     A closed, two-dimensional or flat figure is called a plane shape.
                     Plane figures made of lines are called polygons.
                     Triangle and squares are examples of polygons. Examples of 2-d figures:













                     All the objects that occupy some shape and have three dimensions- length,
                       breadth and height or depth are called as solid shapes. Examples of 3D
                       shapes:















                    Faces, Edges and Vertices

                     Let us consider a cube.
                     Each side of the cube is a flat surface called a flat face or simply a face.
                     When two faces meet at a line segment then it is called an edge.
                     Three edges meet at a point called a vertex.















               Example: How many faces, edges and vertices are in a cylinder?
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