document.write( "Question 175240: Solve algebraically and check your potential solutions: squareroot:x+2-x=0 \n" ); document.write( "
Algebra.Com's Answer #130328 by solver91311(24713)\"\" \"About 
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It really depends on whether you mean \"sqrt%28x%29%2B2-x=0\" or \"sqrt%28x+%2B+2%29+-+x=0\". You could also have meant \"sqrt%28x+%2B+2+-x%29=0\" but that reduces to the absurdity that \"sqrt%282%29+=0\", so I am discounting that possibility.\r
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\n" ); document.write( "\n" ); document.write( "Case 1:\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%28x%29%2B2-x=0\"\r
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\n" ); document.write( "\n" ); document.write( "Let \"t=sqrt%28x%29\", then \"t+%2B+2+-+t%5E2=0\"\r
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\n" ); document.write( "\n" ); document.write( "In standard form: \"t%5E2+-+t+-+2+=+0\".\r
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\n" ); document.write( "\n" ); document.write( "This factors to: \"%28t+-+2%29%28t+%2B+1%29=0\" so \"t+=+2\" or \"t+=+-1\"\r
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\n" ); document.write( "\n" ); document.write( "But \"t=sqrt%28x%29\" so \"sqrt%28x%29+=+2\" or \"sqrt%28x%29+=+-1\" meaning:\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+4\" or \"x+=+1\"\r
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\n" ); document.write( "\n" ); document.write( "However, since we converted to a higher degree equation in order to solve this, we may have introduced an extraneous (and therefore incorrect) root. Check:\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%284%29+%2B++2+-+4+=+2+%2B+2+-+4+=+0\" Checks.\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%281%29+%2B++2+-+1+=+2+%3C%3E+0\" Does not check. Extraneous root.\r
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\n" ); document.write( "\n" ); document.write( "Therefore the solution set is \"x+=+4\"\r
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\n" ); document.write( "\n" ); document.write( "Case 2:\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%28x+%2B+2%29+-+x=0\"\r
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\n" ); document.write( "\n" ); document.write( "Add \"x\" to both sides:\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%28x+%2B+2%29+=+x\"\r
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\n" ); document.write( "\n" ); document.write( "Square both sides:\r
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\n" ); document.write( "\n" ); document.write( "\"x+%2B+2+=+x%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "Standard Form:\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2+-+x+-+2+=+0\"\r
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\n" ); document.write( "\n" ); document.write( "Factor:\r
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\n" ); document.write( "\n" ); document.write( "\"%28x+-+2%29%28x+%2B+1%29=+0\"\r
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\n" ); document.write( "\n" ); document.write( "Hence \"x+=+2+\" or \"x+=+-1\"\r
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\n" ); document.write( "\n" ); document.write( "Again, since we squared both sides in the solution process, we have the possibility of an extraneous root.\r
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\n" ); document.write( "\n" ); document.write( "Check:\r
\n" ); document.write( "\n" ); document.write( "\"sqrt%282+%2B+2%29+-+2=+2+-+2+=+0\" Checks\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%28-1+%2B+2%29+-+%28-1%29+=+1+%2B+1+=+2+%3C%3E+0\" Does not check. Extraneous root.\r
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\n" ); document.write( "\n" ); document.write( "Solution set is \"x+=+2\"
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