document.write( "Question 196864This question is from textbook McDougal Littell Algebra 1
\n" ); document.write( ": Please help me solve this equation: x^2+3/5x-1=0\r
\n" ); document.write( "\n" ); document.write( "It is called completing the square and has to do with solving quadratic equations.
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Algebra.Com's Answer #147600 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
First, let's complete the square:\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B%283%2F5%29x-1\" Start with the left side of the given equation.\r
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\n" ); document.write( "\n" ); document.write( "Take half of the \"x\" coefficient \"3%2F5\" to get \"3%2F10\". In other words, \"%281%2F2%29%283%2F5%29=3%2F10\".\r
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\n" ); document.write( "\n" ); document.write( "Now square \"3%2F10\" to get \"9%2F100\". In other words, \"%283%2F10%29%5E2=%283%2F10%29%283%2F10%29=9%2F100\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B%283%2F5%29x%2Bhighlight%289%2F100-9%2F100%29-1\" Now add and subtract \"9%2F100\". Make sure to place this after the \"x\" term. Notice how \"9%2F100-9%2F100=0\". So the expression is not changed.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E2%2B%283%2F5%29x%2B9%2F100%29-9%2F100-1\" Group the first three terms.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B3%2F10%29%5E2-9%2F100-1\" Factor \"x%5E2%2B%283%2F5%29x%2B9%2F100\" to get \"%28x%2B3%2F10%29%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B3%2F10%29%5E2-109%2F100\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So after completing the square, \"x%5E2%2B3%2F5x-1\" transforms to \"%28x%2B3%2F10%29%5E2-109%2F100\". So \"x%5E2%2B3%2F5x-1=%28x%2B3%2F10%29%5E2-109%2F100\".\r
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\n" ); document.write( "\n" ); document.write( "So \"x%5E2%2B%283%2F5%29x-1=0\" is equivalent to \"%28x%2B3%2F10%29%5E2-109%2F100=0\".\r
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\n" ); document.write( "\n" ); document.write( "Now let's solve \"%28x%2B3%2F10%29%5E2-109%2F100=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B3%2F10%29%5E2-109%2F100=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B3%2F10%29%5E2=0%2B109%2F100\"Add \"109%2F100\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B3%2F10%29%5E2=109%2F100\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B3%2F10=0%2B-sqrt%28109%2F100%29\" Take the square root of both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B3%2F10=sqrt%28109%2F100%29\" or \"x%2B3%2F10=-sqrt%28109%2F100%29\" Break up the \"plus/minus\" to form two equations.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B3%2F10=sqrt%28109%29%2F10\" or \"x%2B3%2F10=-sqrt%28109%29%2F10\" Simplify the square root.\r
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\n" ); document.write( "\n" ); document.write( "\"x=-3%2F10%2Bsqrt%28109%29%2F10\" or \"x=-3%2F10-sqrt%28109%29%2F10\" Subtract \"3%2F10\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-3%2Bsqrt%28109%29%29%2F%2810%29\" or \"x=%28-3-sqrt%28109%29%29%2F%2810%29\" Combine the fractions.\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=%28-3%2Bsqrt%28109%29%29%2F%2810%29\" or \"x=%28-3-sqrt%28109%29%29%2F%2810%29\".
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