# Homework Help: Division with variables (I think I'd call this double division)

1. May 25, 2006

### wScott

I don't know how to LaTeX this question so please bare with me:

( ( x / y ) - ( 4y / x ) ) / (x + 2y)

It's two fractions over a binomial.

Hope this isn't to unclear :(

2. May 25, 2006

### Alkatran

Click this for the code to make it:
$$\frac{\frac{x}{y} - \frac{4y}{x}}{x + 2y}$$

Now the question on everyone's mind is: what do you actually have to do with this? Simplify it?

Last edited: May 25, 2006
3. May 25, 2006

### wScott

Yah, sorry about that, and thanks for the LaTeX code. I'm supposed to simplify it but after setting it up like this $$\frac{x}{y} - \frac {4y}{x} \times \frac{x + 2y}{1}$$ (I think that's proper form anyways) I don't know what else to do.

4. May 25, 2006

### Gablar16

dont know if this is right but it looks good to me

First find the comon denominator in the top fraction

{(x^2-4y^2)/(xy)}/(x+2y)
multiply by the inverse

(x^2-4y^2)/(x^2y+2xy^2)

then diference of squares?

(x+2y)(x-2y)/(xy)(x+2y)

then cancel

(x-2y)/xy

Anyone know a good LaTeX tutorial? I would likke to post more and using LaTeX is just so much prettier :)

Last edited: May 25, 2006
5. May 25, 2006

### VietDao29

Please, don't show COMPLETE solution. You can guide him, and should let the OP do it him/herself. Showing solutions can be good in some cases, like when the OP has made a great deal of effort trying to solve the problem, but still cannot get the correct answer. But showing solution without any explanation, or without the OP's having shown his/her work, it can be very bad.
You can take some time to readthe rules.
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There's a sticky Introducing LaTeX Math Typesetting in the board Math & Science Tutorials (the first board from the top). There are 3 pretty good .PDF files there.

6. May 26, 2006

### Gablar16

You are probably right , sorry about that.