Mr. Udon is a student of Mathematics Discipline Of Khulna University. Now, you have to find his student ID by solving the following system of linear equations:
\(\begin{align*} -3x+2y-6z &=6 \\ 5x+7y-5z &=6 \\ x+4y-2z &=8. \end{align*}\)
If the solution satisfies x+y=z, what is the value of x+y?
