Let A = B =

So, AX = B

Or, X = A ^{– 1}B

|A| = – 7

Cofactors of A are

C₁₁ = – 2 C₁₂ = 1

C₂₁ = – 3 C₂₂ = 5

Since, adj A =

(adj A) =

=

Now, A ^{– 1} =

A ^{– 1} =

So, X =

Hence, X =

X =