Help with math Matrices problem

[ThomasHW]

Homework Statement

Find the reduced row echelon form of the following matrix:

<br /> \begin{array}{c}\ \\ \\ \end{array}\;\begin{vmatrix}\;-4 &amp; 0 &amp; 4\;\\\;2 &amp; -4 &amp; 1\\\;-4 &amp; 4 &amp; -2\end{vmatrix}<br />

The Attempt at a Solution

<br /> \begin{array}{c}\ \\ \\ \end{array}\;\begin{vmatrix}\;1 &amp; 0 &amp; 1\;\\\;0 &amp; 1 &amp; \frac{1}{4}\\\;0 &amp; 0 &amp; 1\end{vmatrix}<br />

I've tried it a few times and keep getting that answer. I've inputted that answer and it's wrong. Am I supposed to keep reducing the third row (even though those are constants?)

 

[dontdisturbmycircles]

Look at your last row. It says 0x+0y=1 (Assuming this is an augmented matrix)

 

[ThomasHW]

I figured it out. I was supposed to make the 1 and 1/4 in the third row zero's as well.

 

[HallsofIvy]

Yes, what you showed was "row echelon" form. "Reduced row echelon reduces above the diagonal also. Actually, until you get down to a row all 0s you will have just the identity matrix.

 

[ThomasHW]

I had assumed not to touch the last row because that is usually the row of constants. In this case it wasn't - I had just assumed it was.