Mathematics Enigma

Got this from Attack Of The Show and also Danica McKellar's website(Winnie from The Wonder Years)

Imagine that...

X = 0.99999... (infinite 9s)

then

10X = 10*0.99999... (infinite 9s)
10X = 9.99999... (infinite 9s)

then

10X-X = 9.99999.... - 0.99999....
10X-X = 9
9X = 9

so

X = 1
0.99999... = 1 ????!!!!???