Explain vertices and edges

Answer 1

There are two sets of mathematical explanations about vertices and edges.
1. solids (polyhedrons)
Each "corner" of a solid is a vertex, and the intersection of two surfaces (faces) make and edge.
For example, a cube has 8 vertices, 12 edges, and 6 faces.
The Euler formula relates these three quantities:
V + F = E + 2

2. Graph theory
A graph is a collection of vertices and edges, or G={V,E} where V is a set of vertices, and E is a set of edges. An edge joins two vertices, and is defined as e=(v1,v2).
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