Im drawíng triangles as polylines, and i need to assigne names to the different sides, is it possible to assigne names automaticly?

Do you want named parameters or just text labels? It is not possible to do this with the standard AutoCAD functionality but you can use a simple LISP macro for this.

Hi Vladimir
 
Thanks.
 
I just wants text labels, is that possible in autocad? Its just to differ the sides in triangles with same leg length.

We have added the labeling option to out TRIANGLE utility - see the Download page.
 
Just appload TRIANGLE.VLX, start the TRIANGLE command and use the Label option "VS" to label vertices and sides of the created triangles. The label text height is controlled by [VAR]TEXTSIZE[/VAR]. You can predefine labelling by:
(setq df:TriangleLabel "VS")