Answer:
The value of det (3A) is -108.
Step-by-step explanation:
If M is square matrix of order n x n, then
[tex]|kA|=k^n|A|[/tex]
Let as consider a matrix A or order 3 x 3. Using the above mentioned property of determinant we get
[tex]|kA|=k^3|A|[/tex]
We need to find the value of det(3A).
[tex]|3A|=3^3|A|[/tex]
[tex]|3A|=27|A|[/tex]
It is given that the det(A)= -4. Substitute |A|=-4 in the above equation.
[tex]|3A|=27(-4)[/tex]
[tex]|3A|=-108[/tex]
Therefore the value of det (3A) is -108.
