I have a question on universal gravitation, it's sort of really hard, especially since i forgot some math rules.(adsbygoogle = window.adsbygoogle || []).push({});

At a certain point between the Earth and the Moon, the net gravitational force exerted on an object by Earth and the Moon is zero. The Earth-moon centre to centre separation is 3.84 x 10^8m. The mass of the moon is 1.2% the mass of the earth.

a) Where is this point located? Are there any such points?

I know there are points because theres an answer. Anyways heres what i did.

FG=0

GMem/(Re-m)^2=G x 0.012Me x m/(Rm-m)^2

After cancelling everything out. I do this:

1/(Re-m)^2= 0.012Me/(Rm-m)^2

Now i still have two unknowns so i solve for Rm-m

(3.84 x 10^8 - Re-m)^2= 0.012Re-m^2

Heres my problem i dont know how what to do with the bracket. If i expand it and then do quadratic formula i dont get the right answer.

So can anyone please help me and tell me if i did anything wrong.

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# Homework Help: Really need help

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