SOLUTION: Solve using Matrices -4x=12 -2x+y-2z=1 2x+2y+2z=8

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Question 1051700: Solve using Matrices
-4x=12
-2x+y-2z=1
2x+2y+2z=8
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Simplified form of the system: system%28x=-3%2C2x-y%2B2z=-1%2Cx%2By%2Bz=4%29



system%28RowOperations%2CR1%2CR2-2%2AR1%2CR3-R1%29



NextOperationIs%2CR1%2C%28-1%29R2%2CR2%2BR3



I will let YOU do the last row operation. It should be add some multiple of row 3 to row 2 to eliminate the coefficient on z.
How do you start with 3 and get 2?
3%2Av=2
v=2%2F3
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Row 3 to be used as system%28%282%2F3%293%2C%282%2F3%29%2A10%29,
system%282%2C20%2F3%29
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The operation to do then is to change row 2 according to R2%2B%282%2F3%29%2AR3.

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