One way: First select the rectangular range of cells. Then move the cursor
near an edge of the selection. When the cursor turns into a four-arrow
shape, click and drag the entire range to a new location.
Select or hi-light the matrix. You then move the cursor to the very edge of
the hi-lighted area. The fat plus will become a thin plus with arrow heads.
You can then click drag and drop the matrix as a unit.