We can think of this as a graph. The base is the origin (0,0).
Distance east is the x coord and distance north is the y coord.
Distance west is negative x and distance south is negative y.
Reed’s final position is (24,-30) and Skylar’s is (-12,43).
The vertical distance between the two is 43-(-30)=73. The horizontal distance is 24-(-12)=36.
The straight line distance between is given using Pythagoras Theorem: √(36²+73²)=√6625=81.39 feet approximately.