To rotate the figure 180 degrees, you would make it so all the points are:
(x,y) to (-x,-y)
Basically, you would switch every sign on the point.
(1,-1) -> (-1,1)
(3,-2) -> (-3,2)
(3,-4) -> (-3,4)
Those new points would be P'Q'R'.
Then when you reflect over the x-axis, you would flip every y sign.
(-1,1) -> (-1,-1)
(-3,2) -> (-3,-2)
(3,-4) -> (3,4)
You would chart those points as P"Q" R".
I hope this helps! (review my answers)
Sorry this took so long!