linear equation matrix method

[wolfcruz]

2x - 1y + 2z = 3
-x + 2y - 1z = 0
3y - 2z = 1
x + y - z = 1

{2 -1 2 3}
{-1 2 -1 0}
{0 3 -2 1}
{1 1 -1 1}

i'm having trouble finding x, y and z. i can only get so far then get lost. if anyone can help me it would be appreciated to see how to do this. thanks.

 

[tkhunny]

Excellent, show us how far you get and we will help you get re-started.

Did you notice that this system may be Over Defined?

RBGTHGANH

 

[wolfcruz]

i did not notice that.
but this is what i got so far before i get stuck.
Add R2 to R1
{1 1 1 3}
{-1 2 -1 0}
{0 3 -2 1}
{1 1 -1 1}
Add r4 to r2
{1 1 13}
{0 3 -2 1}
{0 3 -2 1}
{1 1 -1 1}
-r1 x r4 +r1
{1 1 13}
{0 3 -2 1}
{0 3 -2 1}
{0 0 2 0}

 

[tkhunny]

Good.

Two things:

1) You DO have to write down the correct problem. Good work on the "0x" in row 3. But, that "2x" in row 1 is a bit lacking.
2) The final form you have posted is wonderfully informative. Look really hard at rows 2 and 3 and tell me what they are saying to you.