Mathematical Proof That  2 = 1
Searching for a math impossibility

Try this one out - see if you can find the hole here!
(Don’t scroll down until you’ve given it a good shot ...)

Initial supposition    x = y
Multiply both sides by x:     xx = xy
Subtract y squared from both sides:     xx - yy = xy - yy
Factor both sides:     (x + y)(x - y) = y(x - y)
Divide both sides by (x - y):     x + y = y
Substitute y for x, based on initial supposition:     y + y = y
Replace y with any number (eg. 1):     1 + 1 = 1 or 2 = 1

Scroll down to see the ‘flaw’ ...

The step that divides through by (x - y) is effectively dividing by zero, based on the initial supposition. That invalidates the subsequent results.

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