document.write( "Question 895892: Please help me:
\n" ); document.write( "a=b
\n" ); document.write( "a2=b2
\n" ); document.write( "a2-b2=ab-b2 \n" ); document.write( "

Algebra.Com's Answer #543099 by Edwin McCravy(20060) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "This the famous bogus proof that 2=1.  \r\n" );
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document.write( "1.                  We can have two variables equal to each other.\r\n" );
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document.write( "2.                We multiply both sides by a.\r\n" );
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document.write( "3.         We subtract  from both sides\r\n" );
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document.write( "4.     We factor both sides. \r\n" );
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document.write( "5.                We divide both sides by (a-b)\r\n" );
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document.write( "6.                We substitute b for a since a=b\r\n" );
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document.write( "7.                 We combine like terms on the left\r\n" );
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document.write( "8.                  We divide both sides by b\r\n" );
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document.write( "It looks as though we have proved this proves that 2 equals 1.  But there is a\r\n" );
document.write( "flaw. The flaw is in step 5.  The rule for dividing both sides of an equation\r\n" );
document.write( "is: \r\n" );
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document.write( "\"Both sides of an equation can be divided by the same non-zero number.\"\r\n" );
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document.write( "However (a-b) is zero in disguise because a = b.  So step 5 is an error.\r\n" );
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document.write( "Edwin

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