Matrix A = new Matrix(new double[][] { {2, -1}, {4, 6}}); Matrix B = new Matrix(new double[][] {{1}, {8}}); Matrix X = A.solve(B); System.out.println("Solution using JAMA: " + X); double[][] coefficients = {{2, -1}, {4, 6}}; double[] constants = {1, 8}; double[] result = new double[2]; RealMatrix coefficientMatrix = MatrixUtils.createRealMatrix(coefficients); RealVector constantVector = MatrixUtils.createRealVector(constants); result = new LUDecomposition(coefficientMatrix).getSolver().solve(constantVector); System.out.println("Solution using Java Standard Library: " + Arrays.toString(result));