If two sides of a triangle are 8 cm, 11 cm, then the possible length of the third side is

In $\mathit{∆}ABC$

Sum of two sides > third side 

Difference of two sides < third side 

Given two sides are 8cm, 11cm 

11 + 8 > third side 

19 >  third side 

And 

11 − 8 <  third side 

3 <  third side 

In both two cases possible length of $3^{\mathrm{rd}}$ side is = 8cm