Two satellites revolve around a planet in coplanar circular orbits...

${T}_{1} = 1$ hour

$⇒ {\omega}_{1} = = 2\pi rad / hour$

${T}_{2} = 8$ hours

$⇒ {\omega}_{2} = \dfrac{\pi}{4}rad / hour$

${R}_{1} = 2 \times {10}^{3}km$

As ${T}^{2} ∝ {R}^{3}$

$⇒ {\left(\dfrac{{R}_{2}}{{R}_{1}}\right)}^{3} = {\left(\dfrac{{T}_{2}}{{T}_{1}}\right)}^{2} ⇒ \dfrac{{R}_{2}}{{R}_{1}} = {\left(\dfrac{1}{8}\right)}^{2 / 3} = 4 ⇒ R = 8 \times {10}^{3}km$

${V}_{1} = {\omega}_{1}{R}_{1} = 4\pi \times {10}^{3}km / h$

${V}_{1} = {\omega}_{2}{R}_{2} = 2\pi \times {10}^{3}km / h$

Relative $\omega = \dfrac{{V}_{1} - {V}_{2}}{{R}_{2} - {R}_{1}} = \dfrac{2\pi \times {10}^{3}}{6 \times {10}^{3}}$$= \dfrac{\pi}{3}rad / hour$

$x = 3$