# Homework Help: Rearranging to solve an equation (quick question)

1. Jan 10, 2012

### Yaaaldi

1. The problem statement, all variables and given/known data

Say I had x = y-2 / y + 3

How would I go about rearranging for y= ?

I cant think how to simplify it down to a single y term.

2. Jan 10, 2012

### spamiam

If you don't know how to start, just trying playing around with it. My first step would be to get rid of the y+3 in the denominator.

3. Jan 10, 2012

### bigfooted

Multiply all terms by y.
You then have a second degree polynomial in y, which can be solved in the usual manner (assuming y does not depend on x).

4. Jan 10, 2012

### spamiam

This seems unnecessary to me. One can solve this simply by multiplying and factoring.

5. Jan 10, 2012

### Staff: Mentor

I'm assuming you mean x = (y - 2)/(y + 3). What you wrote is actually x = y - (2/y) + 3.

The lesson is: USE PARENTHESES!

6. Jan 10, 2012

### rollcast

Or use LATEX.

7. Jan 10, 2012

### eumyang

I'm assuming that bigfooted read the problem as x = y - (2/y) + 3. If it is supposed to be x = (y - 2)/(y + 3) then of course multiplying and factoring would be the way to go.