document.write( "Question 241759: 5y(y + 9) = 6(y + 9) \n" ); document.write( "
Algebra.Com's Answer #177051 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"5y%28y+%2B+9%29+=+6%28y+%2B+9%29\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"5y%5E2%2B45y+=+6y+%2B+54\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"5y%5E2%2B45y-6y-54=0\" Get every term to the left side.\r
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\n" ); document.write( "\n" ); document.write( "\"5y%5E2%2B39y-54=0\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "Notice that the quadratic \"5y%5E2%2B39y-54\" is in the form of \"Ay%5E2%2BBy%2BC\" where \"A=5\", \"B=39\", and \"C=-54\"\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-%2839%29+%2B-+sqrt%28+%2839%29%5E2-4%285%29%28-54%29+%29%29%2F%282%285%29%29\" Plug in \"A=5\", \"B=39\", and \"C=-54\"\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-39+%2B-+sqrt%28+1521-4%285%29%28-54%29+%29%29%2F%282%285%29%29\" Square \"39\" to get \"1521\". \r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-39+%2B-+sqrt%28+1521--1080+%29%29%2F%282%285%29%29\" Multiply \"4%285%29%28-54%29\" to get \"-1080\"\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-39+%2B-+sqrt%28+1521%2B1080+%29%29%2F%282%285%29%29\" Rewrite \"sqrt%281521--1080%29\" as \"sqrt%281521%2B1080%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-39+%2B-+sqrt%28+2601+%29%29%2F%282%285%29%29\" Add \"1521\" to \"1080\" to get \"2601\"\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-39+%2B-+sqrt%28+2601+%29%29%2F%2810%29\" Multiply \"2\" and \"5\" to get \"10\". \r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-39+%2B-+51%29%2F%2810%29\" Take the square root of \"2601\" to get \"51\". \r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-39+%2B+51%29%2F%2810%29\" or \"y+=+%28-39+-+51%29%2F%2810%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%2812%29%2F%2810%29\" or \"y+=++%28-90%29%2F%2810%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"y+=+6%2F5\" or \"y+=+-9\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"y+=+6%2F5\" or \"y+=+-9\"
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