The given equations are:

4x+2y-z=4

2x-3y+2z=4

x+y-z= -1

By Adding all the three equations, we have

7x=7, hence x=1.

Substituting for x, the first and the last equations become

2y-z=0 and

y-z= -2

2y-z=0, gives z=2y. Now Substituting for z in y-z=-2,

y-2y= -2

-y= -2

Or, y=2

Hence z=4

Thus x=1, y=2 and z=4

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