A+2b=2a+b=>1=2. please tell me what is the problem

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The discussion centers on a mathematical error in the manipulation of the equation a + 2b = 2a + b, which leads to the incorrect conclusion that 1 = 2. The mistake arises when dividing by a - b, which equals zero if a = b, thus making the division invalid. The thread emphasizes that the equality ax = bx only holds true if x is nonzero. The correct approach involves factoring out (a - b)x = 0, leading to the conclusion that either a = b or x = 0. This highlights the importance of not dividing by zero in algebraic manipulations.
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if we get:

a+2b=2a+b
=>a-b=2a-2b
=>a-b=2(a-b)
=>1=2

I can't figure out the problem in it..please tell me
 
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Does 2*0=3*0 also imply 2=3??
 
waqarrashid33 said:
if we get:

a+2b=2a+b
So 2b- b= 2a- a which gives a= b.

=>a-b=2a-2b
=>a-b=2(a-b)
=>1=2
Since a= b, a- b= 0 and you cannot divide by 0.0

I can't figure out the problem in it..please tell me
 
Note that the law

ax=bx~\Rightarrow~a=b

Only holds if x is nonzero!

The correct way in solving this is

ax=bx~\Rightarrow~ ax-bx=0~\Rightarrow~(a-b)x=0~\Rightarrow ~a-b=0~\text{or}~x=0
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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