Confusion about Row echelon form

Does Row echelon form matrix have only 1s and 0s in the main diagonal? Or does it also have other numbers in the main diagonal?

Also how do i stop the 0 s in the leftmost lower triangle from getting converted to a different number while I am trying to convert the other numbers of the triangle to 0?

Row echelon form has the following characteristics, from the lectures:

  • Zero rows at the bottom
  • Each row has a pivot, which is the leftmost non-zero entry
  • Every pivot to is to the right of the pivot in the row above it.
  • The rank is the number of pivot.
  • in general, pivots greater than one are allowed. This last point answers your question on whether the diagonals can contain numbers other than 0 and 1.

Reduced row echelon form has all pivots equal to 1 and all numbers above a pivot equal to 0.

While trying to change a matrix to its row echelon form, just make sure that you follow the operations that preserve singularity and you are good.