Echelon form

When solving equations, we reduce the matrix to echelon form. It is in echelon form when the first nonzero element, if any, in each row is to the right of the first nonzero element of the previous row

These first nonzero elements will be called ``pivots.''

Example echelon form

Example nonechelon form

Another nonechelon form

You must reduce your systems completely to echelon form. You may not delete any rows as the book says.