#### Question 2

Which of these drawings is a net of a pyramid?

#### Solution

Each of the drawings has 5 faces. If they were to form a pyramid there would be a base and 4 triangles which meet at a vertex.

Each of the nets has a square – this must be the base. The solid must be a square-based pyramid. The triangles must be isosceles.

You will have three faces meeting at each vertex.

This rules out drawings 2 and 3.

Drawing 1 cannot be a pyramid. One reason is that two of the triangles cannot share an edge with the base.

Drawing 4 is the net of a pyramid.

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