# HP F2226A - 48GII Graphic Calculator User Manual Page 358

Graphing calculator.

If you were performing these operations by hand, you would write the
following:
2
A
=
3
aug
4
1
A
0
aug
0
The symbol ≅ (" is equivalent to") indicates that what follows is equivalent to
the previous matrix with some row (or column) operations involved.
The resulting matrix is upper-triangular, and equivalent to the set of equations
which can now be solved, one equation at a time, by backward substitution,
as in the previous example.
Gauss-Jordan elimination using matrices
Gauss-Jordan elimination consists in continuing the row operations in the
upper-triangular matrix resulting from the forward elimination process until an
identity matrix results in place of the original A matrix. For example, for the
case we just presented, we can continue the row operations as follows:
Multiply row 3 by –1/7: 7\Y 3 @RCI!
Multiply row 3 by –1, add it to row 2, replacing it: 1\ # 3
#2 @RCIJ!
4
6
14
1
2
1
3
3
2
1
4
4
2
3
7
1
8
8
24
0
6
13
32
0
1
2
3
A
0
1
1
aug
0
0
7
X +2Y+3Z = 7,
Y+ Z = 3,
-7Z = -14,
2
3
7
2
1
3
2
1
4
2
3
7
1
1
3
6
13
32
7
3
14
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