document.write( "Question 173445: two positive numbers differ by 11, and their square roots differ by 1. Find the numbers. \n" ); document.write( "
Algebra.Com's Answer #128301 by solver91311(24713)\"\" \"About 
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Let's go at this straight up and see what happens:\r
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\n" ); document.write( "\n" ); document.write( "Let one of the numbers be \"x\" and the other one be \"y\", so we know that:\r
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\n" ); document.write( "\n" ); document.write( "\"x-y=11\" and \"sqrt%28x%29-sqrt%28y%29=1\".\r
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\n" ); document.write( "\n" ); document.write( "Yuck! You can see right off that those radicals are going to make this messy.\r
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\n" ); document.write( "\n" ); document.write( "So let's try another tack.\r
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\n" ); document.write( "\n" ); document.write( "Let's keep \"x\" and \"y\" as the desired variables, but let's define two more variables, thus:\r
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\n" ); document.write( "\n" ); document.write( "Let \"t=sqrt%28x%29\" and \"u=sqrt%28y%29\". That means that \"x=t%5E2\" and \"y=u%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "Now we can write:\r
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\n" ); document.write( "\n" ); document.write( "1. \"t%5E2-u%5E2=11\" and\r
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\n" ); document.write( "\n" ); document.write( "2. \"t-u=1\"\r
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\n" ); document.write( "\n" ); document.write( "Solve Eq. 2 for \"t\", \"t=u%2B1\" and substitute this expression for \"t\" in Eq. 1.\r
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\n" ); document.write( "\n" ); document.write( "\"%28u%2B1%29%5E2-u%5E2=11\"\r
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\n" ); document.write( "\n" ); document.write( "Expand the binomial and collect terms:\r
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\n" ); document.write( "\n" ); document.write( "\"u%5E2%2B2u%2B1-u%5E2=11\"\r
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\n" ); document.write( "\n" ); document.write( "\"2u%2B1=11\"\r
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\n" ); document.write( "\n" ); document.write( "\"2u=10\"\r
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\n" ); document.write( "\n" ); document.write( "\"u=5\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"t-u=1\", \"t=6\"\r
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\n" ); document.write( "\n" ); document.write( "But \"x=t%5E2=36\" and \"y=u%5E2=25\"\r
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\n" ); document.write( "\n" ); document.write( "Hence, 36 and 25 are the two numbers.\r
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\n" ); document.write( "\n" ); document.write( "Check:\r
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\n" ); document.write( "\n" ); document.write( "\"36-25=11\"\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%2836%29-sqrt%2825%29=6-5=1\"\r
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\n" ); document.write( "\n" ); document.write( "Answer checks.\r
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