x - y + 5z = 3 .... (1)
4x + z = 0 .......(2)
x + 3y + z = -9 .......(3)
From (2) z = -4x, Substitute for z in (1) and (3):-
x - y + 5(-4x) = 3
-19x + y = 3 ......(4)
x + 3y - 4x = -9
-3x + 3y = -9
- x + y = -3 .....(5)
Subtract:- (4) - (5) we get
-18x = 0
x = 0
So z = -4x = 0
Substituting for x and z in equation (3):-
3y = -9
y = -3
Answer is x = 0 , y = -3 and z = 0