I have a system of linear equations which can be expressed as XA=Y where X and Y are row vectors. The vector Y and the matrix A are given. I need to solve for X. I can rephrase the same equation as AtXt=Yt but the answer will still be the same. I try using matlab to solve for X using the commands X=Y/A or X=Y*inv(A). Matlab do give an answer but it comes with the message "Warning: Matrix is close to singular or badly scaled. Results may be inaccurate. RCOND = 2.336280e-028. " I have check that the determinant of A is not zero although it is near zero. Hence A is not singular. The problem may be due to condition number of the matrix A, I think. What does the RCOND in the message meant? If I still want to solve the equation although the matrix is badly condition, what a better method should I use?