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Original Message (ID '269275') By yehuda:
Dear Hila Once again you encounter the pitfalls of numerical computation. Solve (as well as Reduce) handles this set of equations and constraints easily, and with no error. You used N[Solve[...]] while there are very high powers of the arguments (try Reduce without N, and you will see) So, just replace N[Solve[...]] with N[Solve[...],100] for accuracy of 100 digits and you will be surprised to see that {{Ra -> 95.\ 5701288878973728466744460884528229222834206757770449371053886312318993\ 4299224948287700567097709919, Rr -> 93.34517124624795338466278762681573952065455335207955355279453\ 584905547721535128851234985319798434540}} So the solver keeps the constraints, but numerical computations need to be handled carefully :) yehuda