Transformations, Algebra Trouble

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Linday12
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Homework Statement

If f(x)=[tex]\frac{2x+1}{x+2}[/tex], the equation for y=f^-1(x) is?
So I switch x, x=[tex]\frac{2y+1}{y+2}[/tex]

The Attempt at a Solution


I've tried many ways, but I must be going wrong somewhere, here's what I think to be my nearest:
x(y+2)=2y+1
x(y)+2x=2y+1
x(y)+2x-2x=2y+1-2x
x(y)=2y+1-2x
x(y)-2y=1-2x
And that's as far as I get, it seems I'm stuck in an endless x loop or it simplifies too much to get the correct answer, so I must be missing a vital step or rule.
Sorry, it has been a while since I've done this, and I'm not quite sure if I am even attempting it right. Any tip would be very helpful, I think the answer is:
y=[tex]\frac{1-2x}{x-2}[/tex]

Thank you.
 
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Interesting. Let me see if I understand.

x(y)-2y=1-2x <----Am I to factor(not sure if that's the proper word) the left side to get that final answer then, similar to what you showed?

And then I get y(x-2) after the factor
Which then is y(x-2)=1-2x
And then I can get my final answer of:
y=[tex]\frac{1-2x}{x-2}[/tex]

So that is all I was missing? Then it makes sense now. Thank you very much!