SOLUTION: Please help me this equation step by step: [-5 -1 9 |-2] [1 2 6 |-17] [5 -8 -2 |-3] I don't understand how to get it as 1 0 0 ratio...

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Question 452469: Please help me this equation step by step:
[-5 -1 9 |-2]
[1 2 6 |-17]
[5 -8 -2 |-3]
I don't understand how to get it as
1 0 0 ratio...
0 1 0
0 0 1
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
[1 2 0| -5]
[0 9 0| -9]
[0 0 1| -2]
[-5 -1 9 |-2]
[1 2 6 |-17]
[5 -8 -2 |-3]
-----------------
Interchange the 1st and the 2nd row to get:
[1 2 6 |-17]
[-5 -1 9 |-2]
[5 -8 -2 |-3]
-----------------------
Add 5 times the 1st row to the 2nd row.
Add -5 times the 1st row to the 3rd row.
-----------------------
[1 2 6 |-17]
[0 9 39|-87]
[0 -18 -32|82]
---------------------
Add 2* the 2nd row to the 3rd to get:
[1 2 6 |-17]
[0 9 39|-87]
[0 0 46|-92]
-------------------
Divide thru the 3rd row by 46 to get:
[1 2 6 |-17]
[0 9 39|-87]
[0 0 1| -2]
----------------------
Add -39 times the 3rd row to the 2nd row
Add -6 times the 3rd row to the 1st row
--------------------------
[1 2 0| -5]
[0 9 0| -9]
[0 0 1| -2]
-----------------
Divide thru the 2nd row by "9":
---------------------------------
[1 2 0| -5]
[0 1 0| -1]
[0 0 1| -2]
----------------------------
Add -2 times the 2nd row to the 1st row:
[1 0 0| -3]
[0 1 0| -1]
[0 0 1| -2]
==========================
Cheers,
Stan H.
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