There are three types of elementary row operations in Gauss–Jordan elimination:
- Swapping two rows,
- Multiplying a row by a nonzero number,
- Adding a multiple of one row to another row.
From my understanding Gauss–Jordan elimination works precisely because it doesn't change the underlying linear transformation the original matrix represents.
I guess it's intuitively clear to me how 1 and 2 will not change the underlying linear transformation, but the 3rd one is not so trivial to reason about.
So my question is - am I right that none of the elementary row operations in Gauss–Jordan elimination change the underlying linear transformation? And is there a way to present more intuitively why adding a multiple of one row to another row does not change the linear transformation?