a=b /∙a
a^2=ab /-b^2
a^2-b^2=ab-b^2 factorize
(a-b)(a+b)=b(a-b) /÷(a-b)
a+b=b replace the a by a b, as a=b
b+b=b
2b=b /÷ b
2=1
Q.E.D
Detect the Fallacy
Have fun messing with your friends
please
first line you set a=b
thus (a-b)=0
4th line you divide by (a-b), i.e. you divide by 0. This is undefined.
