I'm having trouble reading this matrix:

1 0 0 4 -1

0 1 0 2 6

0 0 1 3 2

x1 = -1

x2 = 6

x3 = 2

Is this correct? The 4,2,3 column confuses me.

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- Jan 14th 2010, 10:55 AMthekrown[SOLVED] Solutions of four linear systems
I'm having trouble reading this matrix:

1 0 0 4 -1

0 1 0 2 6

0 0 1 3 2

x1 = -1

x2 = 6

x3 = 2

Is this correct? The 4,2,3 column confuses me. - Jan 14th 2010, 12:21 PMbletchley
Looks like an augmented matrix to me. A matrix of that form generally represents 3 equations with 4 variables.

$\displaystyle

1x_1 + 0x_2 + 0x_3 + 4x_4 = -1

$

$\displaystyle

0x_1 + 1x_2 + 0x_3 + 2x_4 = 6

$

$\displaystyle

0x_1 + 0x_2 + 1x_3 + 3x_4 = 2

$ - Jan 14th 2010, 12:42 PMthekrown
Yes indeed, it had slipped my mind. I totally forgot to isolate the x1,2,3 and bring the free variable to the other side. Thank you.