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Pyramid

Pyramid is a solid shape whose base is any polygon, and other faces are triangles that has a common
vertex. The number of faces, vertices, and edges depends on the number of sides of the polygonal
base. If a pyramid has an n-sided base, then it has n + 1 faces, n + 1 vertices, and 2n edges.
Some types of pyramids based on the shape of the base are:

Triangular Pyramid: A triangular pyramid has 4 triangular faces including triangular base.
Edge
Vertex FACTS
A triangular pyramid is also
Face
known as a tetrahedron.
A triangular pyramid has 4 faces (triangular), 6 edges, and 4 vertices.

Square pyramid: A square pyramid has a square base and 4 triangular lateral faces.
Thus, a square pyramid has 5 faces (1 square and 4 triangles), 8 edges and 5 vertices.

Triangular face Vertex
Think and Answer
Have you ever heard about the pyramids
Edges of Egypt? What is the name of the largest

and most famous pyramid? What shape
Square base does it resemble?
Nets of 3-Dimensional Solids

A net is a 2-dimensional (2D) flat structure of a 3-dimensional (3D) object or shape. In other words,
a net is a sort of skeleton outline in 2D, which, when folded, results in a 3D shape.

activity
Take an empty matchbox.
Cut the edges to lay the box flat.
Now, observe what do you get?
The 2-D structure you get is a net of that matchbox.

Since, matchbox is of cuboidal shape. So, the net of a match box also represents a net of cuboidal
shaped objects.

Nets of Cubes and Cuboids

For getting the net of a cube, let us take a cubical box of cardboard. Cut it along its edges so that
all its surfaces can be laid on the floor. Now, what we get is a net of a cube.

Formation of nets of a cubical and a cuboidal object is same.

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