Answer:
This shows 3 pivot position matrixes.
Step-by-step explanation:
The given matrix is:
The option D is correct for this matrix.
The matrix is invertible and the given matrix has 3 pivot positions.
The matrix is invertible if its determinant is nonzero.
Multiply the 3rd row by 1/3.we get:
Now, add the first row with third row:
Replace third row by first row:
This shows 3 pivot position matrixes.
Hence, a matrix is invertible and has 3 pivot positions.