Is an endgame with Queen and King vs. two Rooks and King a win for the Queen, a win for the two Rooks, or a draw?
Generally speaking, it's a draw. Most pawnless endgames are drawn, unless one side has a material advantage of more than a minor piece. Either side can win if there are short-term tactics. To check the outcome of a position, you can use an online tablebase. In particular, it's nice to view the longest wins for either side, which are (according to this page) are
[FEN "k2q4/7R/8/8/8/8/8/2K3R1 w - - 0 1"]
(White to move, mate in 29)
[FEN "4r3/8/5Q2/8/5r2/1k6/8/1K6 w - - 0 1"]
(White to move, mate in 49)