SOLUTION: How do you solve this by elimination: 2x + 3y - z = -8 x - y - z = -2 -4x + 3y + z = 6 Thank you!

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Question 275319: How do you solve this by elimination:
2x + 3y - z = -8
x - y - z = -2
-4x + 3y + z = 6
Thank you!
Answer by Greenfinch(383) About Me  (Show Source):
You can put this solution on YOUR website!

2x + 3y - z = -8
x - y - z = -2
-4x + 3y + z = 6
(1 - 2) x + 4y = -6
(1 + 3)-2x +6y = -2
2x + 8y = -12
14y = -14
y = -1
2x - 3 - z = -8
x + 1 - z = -2
-4x -3 +z = 6
2x - z = -5
x - z = -3
-4x + z = 9
4x - 2z = -10
-z = -1
z = 1
2x -3 -1 = -8
2x = -4
x = -2
so x= -2, y = -1, z = 1
Check in 2
-2 + 1 - 1 = -2 OK