The given system can be written as AX = B, where
Thus, A is non-singular, Therefore, its inverse exists.
Therefore, the given system is consistent and has a unique solution given by X = A−1B.
Cofactors of A are
A11 = 20 + 6 = 26,
A12 = − (− 10 + 0) = 10,
A13 = 6 + 0 = 6
A21 = − (− 5 − 3) = 8,
A22 = − 10 − 0 = − 10,
A23 = − (6 − 0) = − 6
A31 = (− 2 + 4) = 2,
A32 = − (− 4 − 2) = 6,
A33 = − 8 − 2 = − 10
