document.write( "Question 60905: Fully Factor. \r
\n" ); document.write( "\n" ); document.write( "1. 3a^2-36a+36
\n" ); document.write( "2. 4(x-3)^2 - 9(x+4)^2\r
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Algebra.Com's Answer #41861 by joyofmath(189)\"\" \"About 
You can put this solution on YOUR website!
\"3a%5E2-36a%2B36\"
\n" ); document.write( "Divide both sides by 3.
\n" ); document.write( "Then you get \"3%28a%5E2-12a%2B12%29\" which doesn't factor any more.\r
\n" ); document.write( "\n" ); document.write( "\"4%28x-3%29%5E2+-+9%28x%2B4%29%5E2\"\r
\n" ); document.write( "\n" ); document.write( "Let A = \"x-3\" and let B = \"x%2B4\"\r
\n" ); document.write( "\n" ); document.write( "Then the expression is this: \"4A%5E2-9B%5E2\"\r
\n" ); document.write( "\n" ); document.write( "Now, \"4A%5E2+=+%282A%29%5E2\" and \"9B%5E2+=+%283B%29%5E2\"\r
\n" ); document.write( "\n" ); document.write( "So, the expression becomes \"%282A%29%5E2-%283B%29%5E2\"\r
\n" ); document.write( "\n" ); document.write( "This is a difference of two squares. \r
\n" ); document.write( "\n" ); document.write( "It's useful to recognize that \"x%5E2-y%5E2\" factors to \"%28x%2By%29%28x-y%29\"\r
\n" ); document.write( "\n" ); document.write( "So, our expression becomes \"%282A%2B3B%29%282A-3B%29\"\r
\n" ); document.write( "\n" ); document.write( "Now, plug in A = \"x-3\" and B = \"x%2B4\" into the expression.\r
\n" ); document.write( "\n" ); document.write( "You get \"%282%28x-3%29%2B3%28x%2B4%29%29%282%28x-3%29-3%28x%2B4%29%29\"
\n" ); document.write( "Multiply things out to get \"%282x-6%2B3x%2B12%29%282x-6-3x-12%29\"
\n" ); document.write( "Collect like terms and you get \"%285x%2B6%29%28-x-18%29\"\r
\n" ); document.write( "\n" ); document.write( "It's nice to move the minus sign out of the equation.\r
\n" ); document.write( "\n" ); document.write( "The answer then is \"-%285x%2B6%29%28x%2B18%29\"
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