STEP - BY - STEP EXPLANATION
What to find?
• The system of equation of the argumented matrix.
,
• The resultant after the given row operations.
Given:
The system of equation is:
7x - 7y + z = -5
3x - 3y + 8z = -5
-6x + y + 3z = 7
Hence, the correct option is D
The following row operations are to be performed;
[tex]\begin{gathered} R_1=-2r_2+r_1 \\ \\ R_3=2r_2+r_3 \end{gathered}[/tex]
The first row operation implies that you will multiply row 2 by -2 and then add to row. The resultant gives a new row 1.
This means that the elements in row 1 becomes:
Row 1 : 1 -1 - 15 | 5
Row 2: 3 -3 8 | -5
As for row 3, we will multiply row 2 by 2 and then add to row 3 to get a new row 3.
That is;
Row 3 : 0 -5 19 | -3
ANSWER
Option D
Part B
[tex]\begin{bmatrix}{1} & {-1} & {-15\text{\mid}} & {5} \\ {3} & {-3} & {8\text{ }}| & {-5} \\ 0{} & -5{} & {19\text{ }|} & {-3} \\ {\placeholder{⬚}} & {\placeholder{⬚}} & {\placeholder{⬚}} & {\placeholder{⬚}}\end{bmatrix}[/tex]
1 -1 - 15 | 5
3 -3 8 | -5
0 -5 19 | -3
