You can
put this solution on YOUR website!(A^-1 X)^-1 =A (B^-1 A)^-1
(A^-1 X)^-1(A^-1 X) =(A (B^-1 A)^-1)(A^-1 X)
I =(A (B^-1 A)^-1)(A^-1 X)
A^-1 * I =(A^-1 A (B^-1 A)^-1)(A^-1 X)
A^-1 = ((B^-1 A)^-1)(A^-1 X)
(B^-1 A)A^-1 = ((B^-1 A)(B^-1 A)^-1)(A^-1 X)
(B^-1 A)A^-1 = A^-1 X
A(B^-1 A)A^-1 = A*A^-1 X
A(B^-1 A)A^-1 = X
X = A(B^-1 A)A^-1
So the solution is X = A(B^-1 A)A^-1