Example 4.1.1. Are the graphs below equal? \begin{equation*} G_1 = (\{a,b,c\}, \{\{a,b\}, \{b,c\}\}); \qquad G_2 = (\{a,b,c\}, \{\{a,c\}, \{c, b\}\})\text{.} \end{equation*} Solution.