The terms become quite useful, however, when students try to talk about their observations or their strategies for playing games. Familiarize yourself with these terms so that when students find themselves using round-about awkward constructions to try to explain something, you can supply word that are useful to describe it. Each dot is called a vertex . The plural of vertex is vertices . The lines that connect the vertices are called edges .
Edges can connect any or all of the vertices.
All of the different representations of the same graph, are said to be isomorphic to one another. Sometimes it is not so easy to tell that two graphs are isomorphic. It takes quite a bit of moving edges around to see that the graphs above are isomorphic. Mathematical Objects and their Properties A graph is an example of a mathematical object . A number is the mathematical object that is probably the most familiar to everyone.