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[Hotrod50]

Does anyone know how to use a multi-meter to trace a house wire to see if one end is the same as the other end?  I have to white wrapped 3-wires that run through wall to another place, need to see on the other end which is which.  Thanks

[2k]

If there is no voltage on the wires, twist the 3 wires together, go to other end and put meter on ohms and look for wires that will read close to "0" ohms between each other.

[Foot Loose]

Hot Rod
I'm not sure I follow your question 

[Hotrod50]

Foot, I had two wires running from bathroom wall switch up into the attic.  I wasn't sure which wire was which.

[MIKEYTEE]

2 wires or 2 cables?
Mike
 

[MrSurly]

First, note that you're dangerously close to something dangerous.
Be CERTAIN that the wires you are fooling with are not 'live' before starting this. Maybe even turning off the Main Breaker of the whole place to be sure.
As someone asked: Are you saying that you have two wires, or two Romex cables (white jacket with a black a white and a bare conductor)?

What is it you are hooking up, or changing?

Re-reading, it sounds like you've got two Romex cables and you know where they go...you just need to ID them.
As said above, IF they are DEAD....and neither end is hooked up to anything, you should first check for voltage to verify there is none. Then use the OHM setting to see if there is continuity between the black and the bare in either cable.
If not (there shouldn't be***) then go to the other end, (verify no voltage) twist a bare and the black in the same Romex together. Go back to the other end and check for continuity between the black and bare in either Romex. When you see continuity, go back and un-twist them and recheck to verify.
You've got it.
***If there is continuity between the black and any other wire or ground, then the wire IS CONNECTED to something, a light or fan, etc.

[FLY-DOG]

If you're not sure how to use the meter, you could google and probably get a you tube on how to use it. If you know how to use the meter then do as 2K said.

[Hotrod50]

Thanks everyone.  Yes, they were two white Romex cables I ran up the wall into the attic for a bathroom exhaust fan.  I just wasn't sure which was which.. Youtube is great!  Found video of how to use ohm meter.  Worked just like on the video.  Thanks