Coefficient matrix is the phrase that best describes the matrix.
When two matrices are jointly written as a single matrix, then that final matrix is called augmented matrix.
We usually use augmented matrix to do row and column operations faster to reach to the solution of considered system of equation.
The given matrix is as;
[tex]\left[\begin{array}{ccc}-1&-3&-1\\9&-9&-1\\-1&-3&4\end{array}\right][/tex]
Thus, the determinant of the coefficient matrix is 0.
Hence, Coefficient matrix is the phrase that best describes the matrix.
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