document.write( "Question 201632: x^2+x-42=0 \n" ); document.write( "
Algebra.Com's Answer #151861 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2Bx-42=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "Notice that the quadratic \"x%5E2%2Bx-42\" is in the form of \"Ax%5E2%2BBx%2BC\" where \"A=1\", \"B=1\", and \"C=-42\"\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-%281%29+%2B-+sqrt%28+%281%29%5E2-4%281%29%28-42%29+%29%29%2F%282%281%29%29\" Plug in \"A=1\", \"B=1\", and \"C=-42\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%2B-+sqrt%28+1-4%281%29%28-42%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+=+%28-1+%2B-+sqrt%28+1--168+%29%29%2F%282%281%29%29\" Multiply \"4%281%29%28-42%29\" to get \"-168\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%2B-+sqrt%28+1%2B168+%29%29%2F%282%281%29%29\" Rewrite \"sqrt%281--168%29\" as \"sqrt%281%2B168%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%2B-+sqrt%28+169+%29%29%2F%282%281%29%29\" Add \"1\" to \"168\" to get \"169\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%2B-+sqrt%28+169+%29%29%2F%282%29\" Multiply \"2\" and \"1\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%2B-+13%29%2F%282%29\" Take the square root of \"169\" to get \"13\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%2B+13%29%2F%282%29\" or \"x+=+%28-1+-+13%29%2F%282%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2812%29%2F%282%29\" or \"x+=++%28-14%29%2F%282%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+6\" or \"x+=+-7\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x+=+6\" or \"x+=+-7\" \r
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