| Press MATRX, and select EDIT (using the right arrow) | |
| ENTER, 2, ENTER, 3, ENTER to define the dimensions of your matrix | |
| Enter each matrix element. After typing each element, press ENTER. | |
| This defines the matrix [A]. |
We will do a series of elementary row operations on the matrix [A] defined
above to place it in row-echelon form (by forward elimination) and
then reduced row-echelon form (by backward elimination). We
assume [A] has already been defined, as shown above.
| Forward Elimination | |
| MATRIX | |
| Row operation:
Get a 1 in upper left-hand corner byR1ßà R2 |
|
| Select MATH (right arrow), then select rowSwap (down arrow to #8). | |
| ENTER, then MATRX, ENTER (to select matrix [A]) | |
| , 1, 2) ENTER
You now see matrix [A] with its rows swapped. |
|
| Save (store) this matrix (as [A]) to prepare for the next operation.
STO MATRX ENTER ENTER |
|
| Row operation:
Make the 3 a 0 by -3R1 + R2à R2 |
|
| MATRIX, select MATH, select *row+ (#A), ENTER | |
| -3, MATRX ENTER,1,2) | |
| STO MATRX ENTER ENTER | |
| Row operation:
Make the 10 a 1 by (1/10)R2à R2 |
|
| MATRX, select MATH, select *row, ENTER
.1, MATRX ENTER , 2) ENTER STO MATRX ENTER ENTER |
|
| The matrix is now in row-echelon form. | |
| Backward Elimination | |
| Row operation:
Make the -2 (in row 1) a 1 by 2R2 + R1à R1 |
|
| MATRX, select MATH, select *row+, ENTER
2, MATRX ENTER , 2, 1) ENTER STO MATRX ENTER ENTER |
|
| The matrix is now in reduced row-echelon form, and the answer is: x = 3, y = -2 |