The mass of the earth is 81 times that of the moon, and spaceships fly from the earth to the moon The distance between the moon and the earth is 3.84 times 10 to the eighth square meter. It is known that the mass of the earth is about 81 times that of the moon. The spacecraft is attracted by the gravity of the earth and the moon on the way to the moon. When it arrives at a certain area, the resultant force of gravity is equal to zero. How far is this area from the earth

The mass of the earth is 81 times that of the moon, and spaceships fly from the earth to the moon The distance between the moon and the earth is 3.84 times 10 to the eighth square meter. It is known that the mass of the earth is about 81 times that of the moon. The spacecraft is attracted by the gravity of the earth and the moon on the way to the moon. When it arrives at a certain area, the resultant force of gravity is equal to zero. How far is this area from the earth

When the mass M. of the moon is 0, the distance from the spacecraft to the earth is R1, and the distance to the moon is R2
So:
G81Mm/R1^2=GMm/R2^2
R1+R2=3.84*10^8
Then I made an appointment. The calculation is complicated, and the computer is not easy to play