document.write( "Question 837887: What is the solution for x?\r
\n" ); document.write( "\n" ); document.write( "sqrt(x+5)=x^2-5
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Algebra.Com's Answer #521690 by tommyt3rd(5050)\"\" \"About 
You can put this solution on YOUR website!
The solution is very long a little tough...but I will summarize...\r
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\n" ); document.write( "\n" ); document.write( "square both sides to get\r
\n" ); document.write( "\n" ); document.write( "\"%28x%5E2-5%29%5E2=x%2B5\"\r
\n" ); document.write( "\n" ); document.write( "Simplify and rewrite as\r
\n" ); document.write( "\n" ); document.write( "\"P=x%5E4-10x%5E2-x%2B20\"\r
\n" ); document.write( "\n" ); document.write( "We wish to write this as a product of square polynomials, so after some careful thought and experimentation we use\r
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\n" ); document.write( "\n" ); document.write( "\"P=%28x%5E2-a%29%5E2-%28bx%2Bc%29%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "When we expand this version and compare coefficients we can determine that\r
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\n" ); document.write( "\n" ); document.write( "1) \"-2a-b%5E2=-10\"
\n" ); document.write( "2) \"-2bc=-1\"
\n" ); document.write( "3) \"a%5E2-c%5E2=20\"\r
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\n" ); document.write( "\n" ); document.write( "This nonlinear can be solved by substitution. It has a rational solution of \r
\n" ); document.write( "\n" ); document.write( "\"a=9%2F2\"
\n" ); document.write( "\"b=1\"
\n" ); document.write( "\"c=1%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "therefore we can write:\r
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\n" ); document.write( "\n" ); document.write( "\"P=%28x%5E2-9%2F2%29%5E2-%28x%2B1%2F2%29%5E2\"\r
\n" ); document.write( "\n" ); document.write( "and that means\r
\n" ); document.write( "\n" ); document.write( "\"x%5E4-10x%5E2-x%2B20=%28x%5E2-9%2F2%29%5E2-%28x%2B1%2F2%29%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "so that\r
\n" ); document.write( "\n" ); document.write( "\"x%5E4-10x%5E2-x%2B20=%28x%5E2%2Bx-5%29%28x%5E2%2Bx-4%29\"\r
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\n" ); document.write( "\n" ); document.write( "and we know there are only two solutions so...
\n" ); document.write( "\"x=%28-1-sqrt%2817%29%29%2F2\"\r
\n" ); document.write( "\n" ); document.write( "\"x=%281%2Bsqrt%2821%29%29%2F2\"
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