## 2=1?Math brain teasers require computations to solve.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? ## What Next?
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