The first answer.
Point P is at (50,-40) the distance from Q to P is 80 units which you can find by subtracting the x of Q (-30) from the x of P (50).
50-(-30)=80
It then tells you point R is vertically above point Q so you know your x value for R will be the same as Q.
Add your distance from Q to P of 80 units to the y value of Q because you are traveling up.
-40+80=40
R will have a point of (-30,40) and a distance of 80 units