SOLUTION: Solve the system of equations 3x+6y-z=7 3x-3y+5z=-12 9x+9y-2z=12

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Question 352572: Solve the system of equations
3x+6y-z=7
3x-3y+5z=-12
9x+9y-2z=12
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
[A]=%28matrix%283%2C3%2C3%2C6%2C-1%2C3%2C-3%2C5%2C9%2C9%2C-2%29%29
[x]=%28matrix%283%2C1%2Cx%2Cy%2Cz%29%29
[b]=%28matrix%283%2C1%2C7%2C-12%2C12%29%29
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[A][x]=[b]
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[x]=[A]inv[b]
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det([A])=135
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[A]inv=%281%2F135%29%2A%28matrix%283%2C3%2C-39%2C3%2C27%2C51%2C3%2C-18%2C54%2C27%2C-27%29%29
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[x]=%28matrix%283%2C1%2C1%2F9%2C7%2F9%2C-2%29%29