document.write( "Question 1026661: (Factorise) Find the difference of two squares:\r
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Algebra.Com's Answer #641936 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "First learn the principle of factorising \r\n" );
document.write( "the difference of two squares. Here is \r\n" );
document.write( "why it works:\r\n" );
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document.write( "A²-B² = (A-B)(A+B)\r\n" );
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document.write( "Proof: (A-B)(A+B) = A²+AB-AB-B² = A²-B²\r\n" );
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document.write( "So we memorise:\r\n" );
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document.write( "A²-B² is factorized as (A-B)(A+B)\r\n" );
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document.write( "16x²-25y²\r\n" );
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document.write( "Since 16=4² and 25=5², we can rewrite that as\r\n" );
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document.write( "4²x²-5²y²\r\n" );
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document.write( "and again as\r\n" );
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document.write( "(4x)²-(5y)²\r\n" );
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document.write( "Since we have memorized that\r\n" );
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document.write( "A²-B² is factorised as (A-B)(A+B)\r\n" );
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document.write( "We can substitute 4x for A and 5y for B and get that\r\n" );
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document.write( "(4x)²-(5y)² is factorised as (4x-5y)(4x+5y)\r\n" );
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document.write( "Edwin

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