document.write( "Question 1209471: Given that x and y are integers and \"sqrt%282sqrt%2810%29%2B11%29=x%2Bsqrt%28x%2By%29\", find x-y.
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Algebra.Com's Answer #848912 by greenestamps(13203)\"\" \"About 
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\n" ); document.write( "Consider the general expression

\n" ); document.write( "\"%28sqrt%28a%29%2Bsqrt%28b%29%29%5E2\"

\n" ); document.write( "Expanding this, we get

\n" ); document.write( "\"a%2B2sqrt%28ab%29%2Bb\" or \"%28a%2Bb%29%2B2sqrt%28ab%29\"

\n" ); document.write( "Turning this around, we have the general result

\n" ); document.write( "[*] \"sqrt%28%28a%2Bb%29%2B2sqrt%28ab%29%29=sqrt%28a%29%2Bsqrt%28b%29\"

\n" ); document.write( "In this problem, we have the expression

\n" ); document.write( "\"sqrt%2811%2B2sqrt%2810%29%29\"

\n" ); document.write( "Comparing that to the general result[*], we can see by inspection that

\n" ); document.write( "\"sqrt%2811%2B2sqrt%2810%29%29=sqrt%281%29%2Bsqrt%2810%29=1%2Bsqrt%2810%29\"

\n" ); document.write( "The problem asks us to write that in the form

\n" ); document.write( "\"x%2Bsqrt%28x%2By%29\"

\n" ); document.write( "So we want to have

\n" ); document.write( "x = 1 and x+y = 10

\n" ); document.write( "which leads us immediately to

\n" ); document.write( "x = 1 and y = 9.

\n" ); document.write( "Finally, the question asks for the value of x-y.

\n" ); document.write( "ANSWER: x-y = 1-9 = -8
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