document.write( "Question 219573: 4x² + 19x + 21 = 0
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Algebra.Com's Answer #165089 by jim_thompson5910(35256)\"\" \"About 
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\"4x%5E2%2B19x%2B21=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "Notice we have a quadratic equation in the form of \"ax%5E2%2Bbx%2Bc\" where \"a=4\", \"b=19\", and \"c=21\"\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-%2819%29+%2B-+sqrt%28+%2819%29%5E2-4%284%29%2821%29+%29%29%2F%282%284%29%29\" Plug in \"a=4\", \"b=19\", and \"c=21\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-19+%2B-+sqrt%28+361-4%284%29%2821%29+%29%29%2F%282%284%29%29\" Square \"19\" to get \"361\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-19+%2B-+sqrt%28+361-336+%29%29%2F%282%284%29%29\" Multiply \"4%284%29%2821%29\" to get \"336\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-19+%2B-+sqrt%28+25+%29%29%2F%282%284%29%29\" Subtract \"336\" from \"361\" to get \"25\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-19+%2B-+sqrt%28+25+%29%29%2F%288%29\" Multiply \"2\" and \"4\" to get \"8\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-19+%2B-+5%29%2F%288%29\" Take the square root of \"25\" to get \"5\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-19+%2B+5%29%2F%288%29\" or \"x+=+%28-19+-+5%29%2F%288%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-14%29%2F%288%29\" or \"x+=++%28-24%29%2F%288%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+-7%2F4\" or \"x+=+-3\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the answers are \"x+=+-7%2F4\" or \"x+=+-3\" \r
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