Find the radius R of the orbit of a geosynchronous satellite that circles the earth. (Note that R is measured from the center of the earth, not the surface.) You may use the following constants:
The universal gravitational constant G is 6.67*10^11 N*m^2/kg^2 .
The mass of the earth is 5.98*10^24 kg .
The radius of the earth is 6.36*10^6 kg
Radius of the earth is in m not kg, sorry
3 Answers

mv^2/r=GmM/r^2, where M is the mass of the earth.
v^2=GM/r
r=GM/v^2
To find v, we have w=v/r
So v=w*r. w=2*pi/Period. Period is 24 hours=3600*24seconds
Period= 86400s
w=7.27e5
v=7.27e5*r
r=GM/(7.27e5*r)^2
r^3=GM/(7.27e5)^2
r=(GM)^1/3*1/(7.27e5)^2/3
r=4.22e7m=42211.85km
Being the astute student that you are, you’ll recognize this derivation as being quite similar to Kepler’s equation.

A Geosynchronous Satellite

geo sats are 22,000 miles out and how can a radius be in kilograms?
but my guesstimate would be about 25,000 miles