insolvable: not easily solved; "an apparantly insolvable problem"; "public finance had long presented problems unsolvable or at least unsolved"- C L Jones
unresolvable
الواصلة
un·re·sol·va·ble
النطق
علم أصول الكلمات
(prefix.) Middle English, from Old English un-, on-, alteration of and- against; more at ANTE-.