outline of polylines

[DanielErklauer]

I have a street road way shape file (polylines) that I want to create a polygon around the outer exten of it so I can display it on an aerial and set the transparancy so the proposed road way pops out rather than is a linear feature.  I have tried a buffer and that does nto work.  The way that I have been doing it is within CAD I have to close the lines and create a closed polygon, which is extremly time consuming.  Is there a way to create a boundary that follows the outer extent of my road way and creata a polygon?  This way I could over lay my line work on the polgon so that it would pop out.  I have attached a small sample dataset.  Thank you

[EricHajek1]

Have you tried the Minimum Bounding Geometry tool? It's under Data Management and should do almost exactly what you're asking, or at least get close enough that a few hand edits would finish it out.

[DanielErklauer]

yeah that does not work it quicker to do it in CAD.  Thank you.

[KerryShakarjian]

How about changing your display/symbology settings for the line?