SOLUTION: Solve any way you can: 3x - y - 2z = 11 x – 2y + 3z = 12 x + y - 2z = 5 Eric

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Question 297192: Solve any way you can:
3x - y - 2z = 11
x – 2y + 3z = 12
x + y - 2z = 5

Eric
Found 2 solutions by Fombitz, Alan3354:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Using matrix methods,
[A][x]=[b]
[x]=[A]inv[b]
.
.
.
[A]=%28matrix%283%2C3%2C3%2C-1%2C-2%2C1%2C-2%2C3%2C1%2C1%2C-2%29%29
[x]=%28matrix%283%2C1%2Cx%2Cy%2Cz%29%29
[b]=%28matrix%283%2C1%2C11%2C12%2C5%29%29
det[A]= -8
[A]inv=%28-1%2F8%29%2A%28matrix%283%2C3%2C1%2C-4%2C-7%2C5%2C-4%2C-11%2C3%2C-4%2C-5%29%29%0D%0A
and finally,
[x]=%28matrix%283%2C1%2C9%2C6%2C5%29%29

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
x = 9
y = 6
z = 5
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I used an Excel sheet I made that uses determinants.