Let the length of third side be \(x\) \(cm\).
Length of other two side are \(12\) \(cm\) and \(14\) \(cm\).
Now, Perimeter of triangle = \(36\) \(cm\)
\(\Rightarrow 12+14+ x = 36\)
\(\Rightarrow 26+x = 36\)
\(\Rightarrow x = 36-26\)
\(\Rightarrow x = 10\) \(cm\)
Thus, the length of third side is \(10 \;cm\).