Given data:
The first given equation is x-3y+2z=5.
The second given equation is 2x-4y+3z=8.
Third equation is -2x+4y-2z =-12.
Add second and third equations.
[tex]\begin{gathered} (2x-4y+3z)+(-2x+4y-2z)=8-12 \\ z=-4 \end{gathered}[/tex]Substitute -4 for z in first and second equations.
[tex]\begin{gathered} x-3y=13 \\ x=13+3y \\ 2x-4y=20 \\ 2(13+3y)-4y=20 \\ 26+2y=20 \\ 2y=-6 \\ y=-3 \end{gathered}[/tex]The value of x is,
[tex]\begin{gathered} x-3(-3)+2(-4)=5 \\ x=4 \end{gathered}[/tex]Thus, the value of x is 4, the value of y is -3, and the value of z is -4.