My questions is short and to the point: What exactly is a free variable (in a matrix, for example).(adsbygoogle = window.adsbygoogle || []).push({});

How do you know if a variable is free?

Here's a matrix that (apparently) has a free variable:

[1 4 -3 0 0]

[-2 -7 5 1 0 ]

[-4 -5 7 5 0 ]

Row reducing the matrix we end up with:

[1 4 -3 0 0 ]

[0 1 -1 1 0 ]

[0 0 6 -6 0 ]

Apparently this matrix has a variable. Where is it and how do I know that it's free?

Thanks!! :)

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# Homework Help: Free variables in linear algebra?

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