document.write( "Question 266442: solve for x 4x(x-9)-5x(x-8)=-5 \n" ); document.write( "
Algebra.Com's Answer #195740 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"4x%28x-9%29-5x%28x-8%29=-5\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"4x%5E2-36x-5x%5E2%2B40x%2B5=0\" Add 5 to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-x%5E2%2B4x%2B5=0\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "Notice that the quadratic \"-x%5E2%2B4x%2B5\" is in the form of \"Ax%5E2%2BBx%2BC\" where \"A=-1\", \"B=4\", and \"C=5\"\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-%284%29+%2B-+sqrt%28+%284%29%5E2-4%28-1%29%285%29+%29%29%2F%282%28-1%29%29\" Plug in \"A=-1\", \"B=4\", and \"C=5\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-4+%2B-+sqrt%28+16-4%28-1%29%285%29+%29%29%2F%282%28-1%29%29\" Square \"4\" to get \"16\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-4+%2B-+sqrt%28+16--20+%29%29%2F%282%28-1%29%29\" Multiply \"4%28-1%29%285%29\" to get \"-20\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-4+%2B-+sqrt%28+16%2B20+%29%29%2F%282%28-1%29%29\" Rewrite \"sqrt%2816--20%29\" as \"sqrt%2816%2B20%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-4+%2B-+sqrt%28+36+%29%29%2F%282%28-1%29%29\" Add \"16\" to \"20\" to get \"36\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-4+%2B-+sqrt%28+36+%29%29%2F%28-2%29\" Multiply \"2\" and \"-1\" to get \"-2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-4+%2B-+6%29%2F%28-2%29\" Take the square root of \"36\" to get \"6\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-4+%2B+6%29%2F%28-2%29\" or \"x+=+%28-4+-+6%29%2F%28-2%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%282%29%2F%28-2%29\" or \"x+=++%28-10%29%2F%28-2%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+-1\" or \"x+=+5\" Reduce. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x+=+-1\" or \"x+=+5\"
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