From their homes, virtual authorâs assistants organize the publishing process for authors anywhere in the world. A typical day might be on the phone, coordinating the activities of the author and several other professionals, doing research on the Internet and answering and sending emails.
(Jump to Area of a Rectangle or Perimeter of a Rectangle) A rectangle is a four-sided flat shape where every angle is a right angle (90Â°). Opposite sides are parallel and of equal length (so it is a Parallelogram).
A rectangular matrix is in row echelon form if it has the following four properties: 1  All nonzero rows are above any rows of all zeros. 2  Each leading entry of a row is in a column to the right of the leading entry of the row above it.his will make every row start with a 1. The matrix is now in row echelon form: All nonzero rows are above any rows of all zeros (there are no zero rows), each leading entry of a row is in a column to the right of the leading entry of the row above it and all entries in a column below a leading entry are zeros.