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Ok thats very basic but dont get it , I have the following equation $R-A X-B \dfrac{A X}{2 B}=0$ the right result of it is $R- \dfrac{3 A X}{2}=0$

well, now when I attempt to solve it I do the following: $A X+\dfrac{A X}{B}=R$, so what I have done here is cancel the $B$ that is multiplying with one of the $B$'s which are dividing, I don't see why that is wrong, but I guess that's where I make the mistake.. Can anyone tell me why please? Cheeers!

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"one of the B's"? There's more than one B dividing? – DJohnM Apr 3 '13 at 0:17
yeah well is divided by 2*B , so B*B, 2 B's. cheers – Maximilian1988 Apr 3 '13 at 0:18
2*B is not the same as B*B. – Code-Guru Apr 3 '13 at 0:29
up vote 1 down vote accepted

2*B is not B squared, it is just 2 times B. So you have one B in the numerator and one in the denominator, and they cancel completely. There is no B left in the denominator after the cancellation. But there is a "2".

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goooosh...embarrassed... :$ ! thaanks – Maximilian1988 Apr 3 '13 at 0:19
I have done things equally embarrassing more times than I can count. – bob.sacamento Apr 3 '13 at 0:21

You have: $$ R - A X - B \cdot \frac{A X}{2 B} = R - A X - \frac{A B X}{2 B} = R - A X - \frac{A X}{2} = R - A X \left(1 + \frac{1}{2} \right) = R - \frac{3 A X}{2} $$

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how did you edit it so it looks that good? – Maximilian1988 Apr 3 '13 at 0:22
Look at the help for formatting, in particular here. You should be able to ask to edit your own post and look at how I wrote it. – vonbrand Apr 3 '13 at 0:24
ok sweet! Ill have a look at it – Maximilian1988 Apr 3 '13 at 0:27
Stupid braino. Thanks, fixed. – vonbrand Apr 3 '13 at 0:31
BTW, your final $X = \dfrac{2 R}{3 A}$. – vonbrand Apr 3 '13 at 0:32

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