document.write( "Question 549931: X^2-13x-12=0
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Algebra.Com's Answer #358208 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-13x-12=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "Notice that the quadratic \"x%5E2-13x-12\" is in the form of \"Ax%5E2%2BBx%2BC\" where \"A=1\", \"B=-13\", and \"C=-12\"\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-%28-13%29+%2B-+sqrt%28+%28-13%29%5E2-4%281%29%28-12%29+%29%29%2F%282%281%29%29\" Plug in \"A=1\", \"B=-13\", and \"C=-12\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2813+%2B-+sqrt%28+%28-13%29%5E2-4%281%29%28-12%29+%29%29%2F%282%281%29%29\" Negate \"-13\" to get \"13\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2813+%2B-+sqrt%28+169-4%281%29%28-12%29+%29%29%2F%282%281%29%29\" Square \"-13\" to get \"169\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2813+%2B-+sqrt%28+169--48+%29%29%2F%282%281%29%29\" Multiply \"4%281%29%28-12%29\" to get \"-48\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2813+%2B-+sqrt%28+169%2B48+%29%29%2F%282%281%29%29\" Rewrite \"sqrt%28169--48%29\" as \"sqrt%28169%2B48%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2813+%2B-+sqrt%28+217+%29%29%2F%282%281%29%29\" Add \"169\" to \"48\" to get \"217\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2813+%2B-+sqrt%28+217+%29%29%2F%282%29\" Multiply \"2\" and \"1\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2813%2Bsqrt%28217%29%29%2F%282%29\" or \"x+=+%2813-sqrt%28217%29%29%2F%282%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x+=+%2813%2Bsqrt%28217%29%29%2F%282%29\" or \"x+=+%2813-sqrt%28217%29%29%2F%282%29\"
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