Write the System in Row Echelon Form?

You've correctly identified WHY the system is not in row echelon form

Putting it in row echelon form may involve a couple of operations--depending on whether you're using a definition of that form (see the source reference, below) that requires the leading coefficient of each row to be 1.

If we don't have that requirement, then you can obtain row echelon form simply by exchanging the top and bottom rows:

4 4 4 0

0 -1 -3 6

0 0 3 -3

If we need each leading coefficient to be equal to 1, from there it's a simple division operation on each row:

1 1 1 0

0 1 3 -6

0 0 1 -1

It looks like you went on (correctly!) to put the system into REDUCED row echelon form. If your answer wasn't accepted by this evidently programmed interface, I can think of two possible reasons:

(1) Perhaps it isn't expecting the reduced version.

(2) Your notation appears inconsistent. I don't know how you were supposed to write it, but you've got parentheses around the last-column number in two rows, and no parentheses at all in the first row.