If A B and C are n x n invertible matrices does the equation
     If A, B, and C are n x n invertible matrices, does the equation C (AB + CX) = I_n have a solution X? If so, find it. If not, explain your reasoning, (note that X is a MATRIX; also, pay attention to left hand vs. right hand multiplication of matrices.) 
  
  Solution
C-1(AB+CX)=In
CC-1(AB+CX)=C In (Multiply both side by C matrix)
(AB+CX)=C ( CC-1=In & C In=C )
CX=C-AB
C-1CX=C-1(C-AB) ( Multiply both side by C-1 matrix)
X= C-1(C-AB) (C-1C =In & In X=X)

