Please help fast! Is this the correct answer

Don't know how to find x given these segment lengths

Aclassmate thinks that solving a system by graphing gives an exact answer when the lines appear to cross at a grid point, but only an approximate answer when they don't. explain why this isn't true.

The equatorial radius of earth is approximately 6 × 10^3 km, while the equatorial radius of saturn is approximately 6 × 10^4 km. which of the following is true? a. the equatorial radius of saturn is approximately one hundred times that of earth. b. the equatorial radius of saturn is approximately ten times that of earth. c. the equatorial radius of earth is approximately one hundred times that of saturn. d. the equatorial radius of earth is approximately ten times that of saturn.