Question

Two sides of a triangle are 12 cm and 14 cm. The perimeter of the triangle is 36 cm. What is its third side?

Answer 1

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 \(10 \;cm\).