In a pyramid, the number of vertices is 1 more than the number of sides of the polygon base, i.e. vertices = n + 1.
Also, the number of faces is 1 more than the number of sides of the polygonal base, i.e. faces = n + 1.
But the number of edges is 2 times the number of sides of the polygonal base, i,e. edges = 2n.
This also satisfies Euler's rule: F + V = E + 2
(n+1) + (n+1) = 2n + 2.
2n + 2 = 2n + 2.