document.write( "Question 318391: Solve the quadratic equation: a^2-3a-28=0 \n" ); document.write( "
Algebra.Com's Answer #227876 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"a%5E2-3a-28=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "Notice that the quadratic \"a%5E2-3a-28\" is in the form of \"Aa%5E2%2BBa%2BC\" where \"A=1\", \"B=-3\", and \"C=-28\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for \"a\":\r
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\n" ); document.write( "\n" ); document.write( "\"a+=+%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( "\"a+=+%28-%28-3%29+%2B-+sqrt%28+%28-3%29%5E2-4%281%29%28-28%29+%29%29%2F%282%281%29%29\" Plug in \"A=1\", \"B=-3\", and \"C=-28\"\r
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\n" ); document.write( "\n" ); document.write( "\"a+=+%283+%2B-+sqrt%28+%28-3%29%5E2-4%281%29%28-28%29+%29%29%2F%282%281%29%29\" Negate \"-3\" to get \"3\". \r
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\n" ); document.write( "\n" ); document.write( "\"a+=+%283+%2B-+sqrt%28+9-4%281%29%28-28%29+%29%29%2F%282%281%29%29\" Square \"-3\" to get \"9\". \r
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\n" ); document.write( "\n" ); document.write( "\"a+=+%283+%2B-+sqrt%28+9--112+%29%29%2F%282%281%29%29\" Multiply \"4%281%29%28-28%29\" to get \"-112\"\r
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\n" ); document.write( "\n" ); document.write( "\"a+=+%283+%2B-+sqrt%28+9%2B112+%29%29%2F%282%281%29%29\" Rewrite \"sqrt%289--112%29\" as \"sqrt%289%2B112%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"a+=+%283+%2B-+sqrt%28+121+%29%29%2F%282%281%29%29\" Add \"9\" to \"112\" to get \"121\"\r
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\n" ); document.write( "\n" ); document.write( "\"a+=+%283+%2B-+sqrt%28+121+%29%29%2F%282%29\" Multiply \"2\" and \"1\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"a+=+%283+%2B-+11%29%2F%282%29\" Take the square root of \"121\" to get \"11\". \r
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\n" ); document.write( "\n" ); document.write( "\"a+=+%283+%2B+11%29%2F%282%29\" or \"a+=+%283+-+11%29%2F%282%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"a+=+%2814%29%2F%282%29\" or \"a+=++%28-8%29%2F%282%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"a+=+7\" or \"a+=+-4\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"a+=+7\" or \"a+=+-4\" \r
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