[tex]F+V=E+2[/tex]
Solve the Euler's formula above to E (Edges)
[tex]\begin{gathered} \text{Substract 2 in both sides of the equation;} \\ \\ F+V-2=E+2-2 \\ F+V-2=E \\ \\ \text{ Rewrite the equation:} \\ \\ E=F+V-2 \end{gathered}[/tex]
Use the given data;
Faces; F=9
Vertices: V=14
[tex]\begin{gathered} E=9+14-2 \\ E=21 \end{gathered}[/tex]
The polyhedron has 21 edges
