The task is to find the original coordinates with the transformed ones given, so you have to apply the inverse of the stated transformations.
Q"( 6,-1),R"(0,-1) and S"(0,-7)
-> rotate 90 anti-clockwise
Q'(1,6), R'(1,0),S'(7,0)
-> translate left by 7 units
Q(-6,6), R(-6,0), S(0,0)
