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Math brain teasers require computations to solve.


Puzzle ID:#2013
Fun:*** (2.33)
Difficulty:** (1.82)
Submitted By:Mogmatt16Ava****!!




Read this following proof carefully.

X=Y Given
X^2=XY Multiply both sides by X
X^2-Y^2=XY-Y^2 Subtract Y^2 from both sides
(X+Y)(X-Y)=Y(X-Y) Factor both sides
(X+Y)=Y Cancel out common factors
Y+Y = Y Substitute in from line (1)
2Y = Y Collect the Y's
2 = 1 Divide both sides by Y

Now obviously, 2 doesn't equal 1. So what's wrong with this proof?

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