Which Method is Correct for Solving Rational Equations?

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SUMMARY

The discussion centers on solving the rational equation \(\frac{3}{x+2}-\frac{1}{x}=\frac{1}{5x}\). Two methods were employed, yielding solutions of \(x = 1\) and \(x = \frac{4}{3}\). The first method was deemed incorrect due to the failure to multiply both sides by \(x(x+2)\), while the second method, despite introducing an extraneous solution, correctly identified \(x = \frac{4}{3}\) as the valid answer. The conclusion confirms that \(x = \frac{4}{3}\) is the correct solution.

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Homework Statement




photo.jpg


In the picture above, I solved the rational equation using two different methods. In the first method I got x = 1 and in the second method I got x = 4/3. Which answer is correct or are both of them incorrect? Thanks.
 
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If you're going to do your work on paper, and then take a picture of it and upload it, at least do us the courtesy of
1) providing a reasonably decent picture
2) providing a picture that is oriented the right way
 
The rational equation is:
\displaystyle \frac{3}{x+2}-\frac{1}{x}=\frac{1}{5x}\,.​

It's easy to check by plugging in the answers.

[STRIKE]Explain in more detail how you arrived at those answers so we can help you.[/STRIKE]

Added in edit:

Never mind. You do show your work in a hard to read sideways image.

The first method is wrong because you failed to multiply the right side by x(x+2). You must multiply BOTH SIDES of the equation by the same thing.

The second method was OK. You multiplied both sides by an extra x, which gave you an extraneous solution. x=4/3 is correct.
 
Last edited:
EDIT: Yup, 4/3 is the correct answer. Thanks for the help.
 

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