Answer:
[tex] R = 2.1R_{\bigodot} [/tex]
Explanation:
The radius (R) is related to temperature (T) and the luminosity (L) as follows:
[tex] L = T^{4} \times R^{2} [/tex]
By solving the above equation for R we have:
[tex] R = \frac{\sqrt{L}}{T^{2}} [/tex]
With [tex]L = 70L_{\bigodot}[/tex] and [tex]T = 2T_{\bigodot}[/tex] we have:
[tex] R = \frac{\sqrt{70L_{\bigodot}}}{(2T_{\bigodot})^{2}} [/tex]
[tex] R = \frac{\sqrt{70}}{(2)^{2}} [/tex]
[tex] R = 2.1R_{\bigodot} [/tex]
Therefore, the radius is 2.1 times that of the Sun.
I hope it helps you!
