# Math Help - rearranging equation

1. ## rearranging equation

hi how do I rearrange this equation to give me the value of J

G= pi x D^2/ 4JL

Thanks

2. Originally Posted by scarface1
hi how do I rearrange this equation to give me the value of J

G= pi x D^2/ 4JL

Thanks
$G= \pi \times D^2/ 4JL=\frac{\pi D^2}{4JL}$

Now multily both sides by $4JL$ and try to solv it for J

3. i dont quite understand which two sides im supposed to multiply :S
could you possibly explain this step by step please

Thank you so much

4. If i'm reading the question correctly, it's $G=\frac{\pi(D^2)}{4JL}$

So;

$\pi(D^2)=4GJL$

$\frac{\pi(D^2)}{4GL}=J$

5. You would cross multiply and solve for $J$