document.write( "Question 236208: 4y^2-7y-15=0 \n" ); document.write( "
Algebra.Com's Answer #173897 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"4y%5E2-7y-15=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "Notice that the quadratic \"4y%5E2-7y-15\" is in the form of \"Ay%5E2%2BBy%2BC\" where \"A=4\", \"B=-7\", and \"C=-15\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for \"y\":\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%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( "\"y+=+%28-%28-7%29+%2B-+sqrt%28+%28-7%29%5E2-4%284%29%28-15%29+%29%29%2F%282%284%29%29\" Plug in \"A=4\", \"B=-7\", and \"C=-15\"\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%287+%2B-+sqrt%28+%28-7%29%5E2-4%284%29%28-15%29+%29%29%2F%282%284%29%29\" Negate \"-7\" to get \"7\". \r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%287+%2B-+sqrt%28+49-4%284%29%28-15%29+%29%29%2F%282%284%29%29\" Square \"-7\" to get \"49\". \r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%287+%2B-+sqrt%28+49--240+%29%29%2F%282%284%29%29\" Multiply \"4%284%29%28-15%29\" to get \"-240\"\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%287+%2B-+sqrt%28+49%2B240+%29%29%2F%282%284%29%29\" Rewrite \"sqrt%2849--240%29\" as \"sqrt%2849%2B240%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%287+%2B-+sqrt%28+289+%29%29%2F%282%284%29%29\" Add \"49\" to \"240\" to get \"289\"\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%287+%2B-+sqrt%28+289+%29%29%2F%288%29\" Multiply \"2\" and \"4\" to get \"8\". \r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%287+%2B-+17%29%2F%288%29\" Take the square root of \"289\" to get \"17\". \r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%287+%2B+17%29%2F%288%29\" or \"y+=+%287+-+17%29%2F%288%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%2824%29%2F%288%29\" or \"y+=++%28-10%29%2F%288%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"y+=+3\" or \"y+=+-5%2F4\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"y+=+3\" or \"y+=+-5%2F4\" \r
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