I just know that it takes 6 hours for the satellite to pass between each quarter.
Hint: Use the parametric form of the circle \((x,y) = (42000 \cos \theta, 42000 \sin \theta)\)
Assuming that it moves in a counter-clockwise direction
Note that in 6 hrs it is at 90°....so...in 5 hrs it must be at (5/6)90° = 75°
r = 42000
So the position at 5 hrs = ( r cos 75° , r sin 75°) = (42000cos 75° , 42000sin75° )
I'll let you finsih this......