How do I remove $y$ from $xy$ in $y=xy-2x$?

Question

I got an inverse function $y=xy-2x$. But how do I remove $y$ from $xy$?

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score 2 · Accepted Answer · answered Oct 15 '18 at 06:56

2

You can write $$y-xy=-2x$$ and $$y(1-x)=-2x$$ so $$y=\frac{-2x}{1-x}$$ for $x\ne 1$

answered Oct 15 '18 at 06:56

Thanks @Dr. Sonnhard Graubner! – Kakeru Oct 15 '18 at 06:57
What if $x$ ≠ 2? – Kakeru Oct 15 '18 at 06:57
This can be then you divide not by $0$ – Dr. Sonnhard Graubner Oct 15 '18 at 06:59
So just don't divide it by $0$ right? – Kakeru Oct 15 '18 at 07:00
Only in the case of $x=1$ – Dr. Sonnhard Graubner Oct 15 '18 at 07:01
So you mean that when $x=1$ you don't divide by $0$ but you do in the other cases? – Kakeru Oct 15 '18 at 07:04
Only in the case when $x=1$ you divide by $0$ and in no other case – Dr. Sonnhard Graubner Oct 15 '18 at 07:09
Oh, ok, thanks for that! – Kakeru Oct 15 '18 at 07:10
@Kakeru: if this answer really helped you, you might consider to accept it. :) – manooooh Oct 15 '18 at 07:50

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