nag_dgbrfs (f07bhc) Example Program Results Solution(s) 1 2 1 -2.0000 1.0000 2 3.0000 -4.0000 3 1.0000 7.0000 4 -4.0000 -2.0000 Backward errors (machine-dependent) 1.1e-16 9.9e-17 Estimated forward error bounds (machine-dependent) 1.6e-14 1.9e-14