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#1 2009-04-15 00:03:32
- Shmeeztut
- Member
- Registered: 2009-04-14
- Posts: 2
Impossible Algebra?
My friend told me about this, and I just don't get how it works!
x = y
Times x to both sides.
x² = xy
Times -y^2 to both sides.
x² - y² = xy - y²
Factorise.
(x + y )(x - y) = y(x - y)
Then... divide both sides by (x - y).
x = x + y?!
How is this possible? The algebra is correct as far as I can see.
da frend hu told mi is super cool and awesome
Last edited by Shmeeztut (2009-04-15 00:06:05)
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#2 2009-04-15 00:10:26
- LuisRodg
- Real Member
- Registered: 2007-10-23
- Posts: 322
Re: Impossible Algebra?
Algebra is not correct. Since x = y then x - y = 0 so when you divide by x - y you are dividing by 0 which is not allowed in math. Thats the mistake.
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