document.write( "Question 513981: what does 2 radical sign 45 minus 2 radical sign 5 equal
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Algebra.Com's Answer #343261 by drcole(72) $\"\"$ $\"About$

You can put this solution on YOUR website!
I think that you are being asked to simplify the expression:\r
\n" ); document.write( "\n" ); document.write( " $\"+2%2Asqrt%2845%29+-+2%2Asqrt%285%29+\"$ \r
\n" ); document.write( "\n" ); document.write( "The important thing to remember here is that you can break up the square root of a product into a product of square roots:\r
\n" ); document.write( "\n" ); document.write( " $\"+sqrt%28ab%29+=+sqrt%28a%29%2Asqrt%28b%29+\"$ \r
\n" ); document.write( "\n" ); document.write( "(Note: it is NOT true that $\"sqrt%28a+%2B+b%29+=+sqrt%28a%29+%2B+sqrt%28b%29\"$ --- for example, $\"sqrt%289+%2B+16%29\"$ does not equal $\"sqrt%289%29+%2B+sqrt%2816%29\"$ )\r
\n" ); document.write( "\n" ); document.write( "We want to break up 45 into a product of a number times a perfect square. One way to do this is:\r
\n" ); document.write( "\n" ); document.write( " $\"45+=+9+%2A+5\"$ \r
\n" ); document.write( "\n" ); document.write( "So $\"sqrt%2845%29+=+sqrt%289+%2A+5%29+=+sqrt%289%29%2Asqrt%285%29+=+3%2Asqrt%285%29+\"$ \r
\n" ); document.write( "\n" ); document.write( "Thus we can rewrite our original expression as:\r
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