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aug
A  
The matrix A
aug
 is the same as the original matrix A with a new row, 
corresponding to the elements of the vector b, added (i.e., augmented) to the 
right of the rightmost column of A.  
 
Once the augmented matrix is put together, we can proceed to perform row 
operations on it that will reduce the original A matrix into an upper-triangular 
matrix.  For this exercise, we will use the RPN mode (H\@@OK@@), with 
system flag 117 set to SOFT menu. In your calculator, use the following 
keystrokes.  First, enter the augmented matrix, and make an extra copy of the 
same in the stack (This step is not necessary, except as an insurance that you 
have an extra copy of the augmented matrix saved in case you make a 
mistake in the forward elimination procedure that we are about to undertake.): 
 
[[2,4,6,14],[3,-2,1,-3],[4,2,-1,-4]] `` 
 
Save augmented matrix in variable AAUG: ³~~aaug~ K 
 
With a copy of the augmented matrix in the stack, press „´ @MATRX! @ROW! 
to activate the ROW operation menu.  Next, perform the following row 
operations on your augmented matrix. 
Multiply row 1 by ½:  2Y 1 @RCI! 
 
Multiply row 1 by –3 add it to row 2, replacing it: 3\ #  1 
#2 @RCIJ! 
 
Multiply row 1 by –4 add it to row 3, replacing it: 
4\#1#3@RCIJ! 
 
Multiply row 2 by –1/8:  8\Y2 @RCI! 
Multiply row 2 by 6 add it to row 3, replacing it: 6#2#3 @RCIJ!