document.write( "Question 196588: Solve algebraically and check your potential solutions: √x+2-x=0 \n" ); document.write( "
Algebra.Com's Answer #147336 by jim_thompson5910(35256)\"\" \"About 
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\"sqrt%28x%2B2%29-x=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%28x%2B2%29=x\" Add \"x\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B2=x%5E2\" Square both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"0=x%5E2-x-2\" Get all terms to one side.\r
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\n" ); document.write( "\n" ); document.write( "Notice we have a quadratic in the form of \"Ax%5E2%2BBx%2BC\" where \"A=1\", \"B=-1\", and \"C=-2\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for x\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-B+%2B-+sqrt%28+B%5E2-4AC+%29%29%2F%282A%29\" Start with the quadratic formula\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-%28-1%29+%2B-+sqrt%28+%28-1%29%5E2-4%281%29%28-2%29+%29%29%2F%282%281%29%29\" Plug in \"A=1\", \"B=-1\", and \"C=-2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%281+%2B-+sqrt%28+%28-1%29%5E2-4%281%29%28-2%29+%29%29%2F%282%281%29%29\" Negate \"-1\" to get \"1\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%281+%2B-+sqrt%28+1-4%281%29%28-2%29+%29%29%2F%282%281%29%29\" Square \"-1\" to get \"1\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%281+%2B-+sqrt%28+1--8+%29%29%2F%282%281%29%29\" Multiply \"4%281%29%28-2%29\" to get \"-8\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%281+%2B-+sqrt%28+1%2B8+%29%29%2F%282%281%29%29\" Rewrite \"sqrt%281--8%29\" as \"sqrt%281%2B8%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%281+%2B-+sqrt%28+9+%29%29%2F%282%281%29%29\" Add \"1\" to \"8\" to get \"9\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%281+%2B-+sqrt%28+9+%29%29%2F%282%29\" Multiply \"2\" and \"1\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%281+%2B-+3%29%2F%282%29\" Take the square root of \"9\" to get \"3\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%281+%2B+3%29%2F%282%29\" or \"x+=+%281+-+3%29%2F%282%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%284%29%2F%282%29\" or \"x+=++%28-2%29%2F%282%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+2\" or \"x+=+-1\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the answers are \"x+=+2\" or \"x+=+-1\" \r
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\n" ); document.write( "\n" ); document.write( "However, if we plug in \"x+=+-1\", we'll find that a contradiction will result. \r
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\n" ); document.write( "\n" ); document.write( "So the only solution is \"x+=+2\"
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