Solve the following using Gauss-Jordan elimination:

I keep setting up augmented matrices but I do not know how to get it to reduced-eschelon form at all.

Edit: I worked this out:

Is this correct?

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- Jun 1st 2009, 01:13 PMPinkkGauss-Jordan Elimination
Solve the following using Gauss-Jordan elimination:

I keep setting up augmented matrices but I do not know how to get it to reduced-eschelon form at all.

Edit: I worked this out:

Is this correct? - Jun 1st 2009, 01:41 PMHallsofIvy
Yes, that is correct! Well, done!

(It took me a moment to figure out where that "r" came from!)

You don't say if you did that by row-reducing the augmented matrix but here's how I did it.

The augmented matrix is

Divide the first row by 2, add the original first row to the second row, and subtract the original first row times 4 from the third row to get

Divide the second row by 7, add the original second row to the third row, and subtract the**new**second row from the first row to get

.

The fact that the last row consists of all "0"s tells us that we will have an infinite number of solutions. From the first equation, so and so . Now let r= z to get your soltutions. - Jun 1st 2009, 01:59 PMPinkk
Bah, forgot to write the for the y part on my paper. (Headbang) And yeah, I meant row-reduced since the following question asks to do it using Gaussian-elimination

Thank you. (Clapping)

And to just check, for Gaussian-elimination it would be: