Interactive Linear Algebra by Dan Margalit and others / Row Reduction

Section of Interactive Linear Algebra by Dan Margalit and others by its whole-book authors Dan Margalit and Joseph Rabinoff; no separate chapter byline or date is asserted.

Online text: textbooks.math.gatech.edu/ila/row-reduction.html

Cited passages: §1.2.1, Augmented Matrices and Row Operations: preservation of solutions; §1.2.2, Echelon Forms: leading entries and reduced form; §1.2.3, definitions of pivot position and pivot column.