Rearranging to solve an equation (quick question)

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Homework Help Overview

The discussion revolves around rearranging the equation x = (y - 2) / (y + 3) to solve for y. Participants explore the implications of the equation's structure and the importance of proper notation.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants suggest manipulating the equation by eliminating the denominator and multiplying terms. There is a debate about the necessity of certain steps, with some questioning whether a simpler method exists. The importance of parentheses in conveying the correct mathematical expression is also highlighted.

Discussion Status

The discussion is active, with various approaches being considered. Some participants provide guidance on manipulating the equation, while others express differing opinions on the methods suggested. The conversation reflects a mix of interpretations regarding the initial equation's format.

Contextual Notes

There is a noted emphasis on the use of parentheses to clarify the equation's structure, as misunderstandings about the expression could lead to different interpretations and approaches.

Yaaaldi
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Homework Statement



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

How would I go about rearranging for y= ?

I can't think how to simplify it down to a single y term.
 
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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.
 
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).
 
bigfooted said:
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).

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

Homework Statement



Say I had x = y-2 / y + 3
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!
 
Mark44 said:
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!

Or use LATEX.
 
bigfooted said:
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).
spamiam said:
This seems unnecessary to me. One can solve this simply by multiplying and factoring.
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.
 

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