0.999....=1

[Peh]

Teeqoz said:

Peh said:

And the winner is this guy.

It's midnight here and I can' think straight. The calculation is wrong in the op. You can't add an x out of nothing on one side and remove 0.9999999. That's the mistake OP did. 

 

So you had to +x on both sides and minus 0.9999 also on both sides. You just can't replace 0,99999 with X. This is not possible.

Yes I can, because I've defined x = 0.999...

 No you can't. Your replacement changes the whole equation. That's not how algebra works. I cannot randomly replace numbers out of the blue. And say x is still what it was in the previous equation. You cannot say 0.9999 is 1 when you changed x to 1.