Do the translation first. The rule is:
T(3,-1)
(x,y) -------------------> (x+3,y-1)
Do the rotation second. Assuming it's about the origin (O), the rule is:
R(270 CW,O)
(x,y) -------------------> (-y,x)
Only you want to do it on the translated coordinates:
R(270 CW,O)
(x+3,y-1) -------------------> (-(y-1), x+3) This is the answer. Plug in (-5,-6) for (x,y).