The network below can be represented as a planar graph.
Draw the planar graph representation of this network and find the number of faces in the planar graph. (3 marks)
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Show Worked Solution
`text(Redrawing the graph in planar form:)`
`text{Method 1}`
`text{Number of faces = 6 (by inspection)}`
`text(Method 2 (Euler’s formula))`
| `v + f` | `= e + 2` |
| `5 + f` | `= 9 + 2` |
| `:. f` | `= 6` |