Find the Proper Time given the time and distance between two events

[zellwwf]

Homework Statement

I have written everything in the attachement, please read it

Homework Equations

I have written everything in the attachement, please read it
all of them :)

The Attempt at a Solution

My solution is also at the PDF attached, just check for correctness, and if i made any mistakes, tell me

 

[voko]

Looking good!

 

[zellwwf]

So Correct :P?
Finaly a correct answer..