You can put this solution on YOUR website! X + 2y - Z = 0
3x + y -2z = 3
2x - z = 0 --> z = 2x
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Sub for z in eqn 1 & 2
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X + 2y - Z = 0 --> -x + 2y = 0
3x + y -2z = 3 --> -x + y = 3
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-x + 2y = 0
-x + y = 3
-------------------- Subtract
y = -3
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-x + y = 3
x = -6
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z = -12