Evidence that two is not equal to one. 2 = 1 .

 

Dos es igual a uno

Obviously two is not equal to one, the show that says otherwise has a hidden error between the lines 4 and 5.
Line 4 - Factoring :
to ( b - a) = (a + b ) ( b - a)
Line 5 - And simplifying the term ( b - a) :
a = a + b
By simplifying the term ( b -a) we do we are divide both sides of equality ( b -a) , or what is the same, divide by zero , invalid operation.
The math does not lie.