How to apply texture to an object face avoiding triangular mesh I am facing a problem, 
as I apply a texture to the detached face of a cube. 

Instead of being spread over the face, 
it is repeated in mesh triangles &amp; is distorted. 



Could you suggest a way to solve this problem?

Thank you!
Select faces, hit U, Unwrap. Google search UV unwrapping, this is an important topic that you should learn and won't be explained in full here.