Answer:
a. No
b. Yes
Step-by-step explanation:
as we know the inverse of the matrix is A⁻¹ = (adjA)/det(A)
If the determinant of the matrix is 0 then the inverse of that matrix does not exists.
For first matrix the determinant is
|A| = [tex](-2*9)-(6*(-3))[/tex]
[tex]=-18-(-18)\\=-18 + 18\\=0[/tex]
Hence the inverse of this matrix does not exists.
|B| = [tex](-2*9)-(6*3)[/tex]
[tex]-36[/tex]
Since the determinant of the matrix in the second option is non-zero .Hence it's inverse exists.