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# 4=3... Where did I go wrong?

### #1

Posted 25 October 2011 - 06:51 PM

Begin with a simple algebraic equation:

a + b = c

Now, replace each letter with 4 of that letter minus 3 of that letter:

4a - 3a + 4b - 3b = 4c - 3c

Rearrange, so that the 4s are on the left and the 3s on the right

4a + 4b - 4c = 3a + 3b - 3c

Simplify by factoring:

4(a + b - c) = 3(a + b - c)

Then divide each side by a+b-c:

4 = 3

Can someone point out the mistake? (an easy one for maths lovers)

### #2

Posted 25 October 2011 - 06:56 PM

### #3

Posted 25 October 2011 - 10:36 PM

**Edited by Thalia, 25 October 2011 - 10:37 PM.**

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Other games:

**The Green Glass Doors**

**Telephone**

### #4

Posted 26 October 2011 - 09:16 PM

### #5

Posted 26 October 2011 - 10:03 PM

to fool the non-mathematical variety of people XDlol, that was really good, i'm going to use that

### #6

Posted 15 November 2011 - 09:52 AM

1. a = b

2. a

^{2}= ab (multiplying a on both sides)

3. a

^{2}- b

^{2}= ab - b

^{2 }(subtracting b

^{2}from both sides)

4. (a+b)(a-b) = b(a-b)

5. a+b = b (divided both sides by (a-b) )

6. 2b = b ( from equation 1 i.e. replacing a=b)

7. 2 = 1

### #7

Posted 16 November 2011 - 08:12 AM

### #8

Posted 22 November 2011 - 12:41 AM

**Edited by Morningstar, 22 November 2011 - 12:42 AM.**

### #9

Posted 16 December 2011 - 10:06 AM

a+b=c => a+b-c = 0

### #10

Posted 24 December 2011 - 01:21 AM

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