I solved a matrix as follows: {{0,1,1},{0,2,4},{0,3,9}}.{{0},{25},{20}} Resulting: {{45},{130},{255}} I tried to use an inverse matrix to solve: Inverse[{{0,1,1},{0,2,4},{0,3,9}}].{{45},{130},{255}} Wishing the following solution: {{0},{25},{20}} But this matrix is singular: How should I proceed?