Justino, Júliavan den Berg, Imme2014-03-182014-03-182012-061081-3810http://hdl.handle.net/10400.26/6101Systems of linear equations, called flexible systems, with coefficients having uncertainties of type o (.) or O (.) are studied. In some cases an exact solution may not exist but a general theorem that guarantees the existence of an admissible solution, in terms of inclusion, is resented. This admissible solution is produced by Cramer’s Rule; depending on the size of the uncertainties appearing in the matrix of coefficients and in the constant term vector some adaptations may be needed.engCramer’s RuleExternal numbersNonstandard analysisjournal article