Answer:
a. [tex]\left[\begin{array}{cccc}9&-4&-5&|9\\7&4&-4&|-1\\6&-6&1&|-5\end{array}\right][/tex]
Step-by-step explanation:
The given system of equation is
[tex]9x-4y-5z=9[/tex]
[tex]7x+4y-4z=-1[/tex]
[tex]6x-6y+z=-5[/tex]
The coefficient matrix is :
[tex]\left[\begin{array}{ccc}9&-4&-5\\7&4&-4\\6&-6&1\end{array}\right][/tex]
The constant matrix is
[tex]\left[\begin{array}{c}9\\-1\\-5\end{array}\right][/tex]
The augmented matrix is obtained by combining the coefficient matrix and the constant matrix.
[tex]\left[\begin{array}{cccc}9&-4&-5&|9\\7&4&-4&|-1\\6&-6&1&|-5\end{array}\right][/tex]
The correct choice is A
