I'm trying to rearrange this equation to isolate r2:(adsbygoogle = window.adsbygoogle || []).push({});

1/2(m2)(v)^2 = [-(G)(m2)(m1)] / (r2) - [-(G)(m2)(m1)] / (r1)

Eliminating m2:

1/2(v)^2 = [-(G)(m1)] / (r2) - [-(G)(m1)] / (r1)

Some swapping around the equal sign:

[(G)(m1)] / (r2) = [(G)(m1)] / (r1) - 1/2(v)^2

Dividing everything by (G)(m1):

1 / (r2) = 1 / (r1) - [(v)^2] / [2(G)(m1)]

Take the reciprocals:

(r2) = (r1) - [2(G)(m1)] / [(v)^2]

This isolates r2, but the answer I get when I substitute the numbers is way off. I'm not 100% confident in my rearranging skills, so I'm pretty sure I've made an error somewhere trying to do so.

So, if someone can point out where I went wrong / which rule of rearranging I may have broken and push me in the right direction, it would be greatly appreciated!

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# Homework Help: Trouble rearranging this equation

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