document.write( "Question 165265: 7.) Solve by completing the square.\r
\n" ); document.write( "\n" ); document.write( "2x^2+x-6=0
\n" ); document.write( " the answer shows -2,3/2 I am not sure how they got the answer?
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Algebra.Com's Answer #121823 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "\"2x%5E2%2Bx-6\" Start with the given expression.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x%5E2%2B%281%2F2%29x-3%29\" Factor out the \"x%5E2\" coefficient \"2\". This step is very important: the \"x%5E2\" coefficient MUST be equal to 1.\r
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\n" ); document.write( "\n" ); document.write( "Take half of the \"x\" coefficient \"1%2F2\" to get \"1%2F4\". In other words, \"%281%2F2%29%281%2F2%29=1%2F4\".\r
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\n" ); document.write( "\n" ); document.write( "Now square \"1%2F4\" to get \"1%2F16\". In other words, \"%281%2F4%29%5E2=%281%2F4%29%281%2F4%29=1%2F16\"\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x%5E2%2B%281%2F2%29x%2Bhighlight%281%2F16-1%2F16%29-3%29\" Now add and subtract \"1%2F16\" inside the parenthesis. Make sure to place this after the \"x\" term. Notice how \"1%2F16-1%2F16=0\". So the expression is not changed.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28%28x%5E2%2B%281%2F2%29x%2B1%2F16%29-1%2F16-3%29\" Group the first three terms.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28%28x%2B1%2F4%29%5E2-1%2F16-3%29\" Factor \"x%5E2%2B%281%2F2%29x%2B1%2F16\" to get \"%28x%2B1%2F4%29%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "\"2%28%28x%2B1%2F4%29%5E2-49%2F16%29\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x%2B1%2F4%29%5E2%2B2%28-49%2F16%29\" Distribute.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x%2B1%2F4%29%5E2-49%2F8\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "So after completing the square, \"2x%5E2%2Bx-6\" transforms to \"2%28x%2B1%2F4%29%5E2-49%2F8\". So \"2x%5E2%2Bx-6=2%28x%2B1%2F4%29%5E2-49%2F8\".\r
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\n" ); document.write( "\n" ); document.write( "So \"2x%5E2%2Bx-6=0\" is equivalent to \"2%28x%2B1%2F4%29%5E2-49%2F8=0\".\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x%2B1%2F4%29%5E2=0%2B49%2F8\"Add \"49%2F8\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x%2B1%2F4%29%5E2=49%2F8\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B1%2F4%29%5E2=%2849%2F8%29%2F%282%29\" Divide both sides by \"2\".\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B1%2F4%29%5E2=49%2F16\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B1%2F4=0%2B-sqrt%2849%2F16%29\" Take the square root of both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B1%2F4=sqrt%2849%2F16%29\" or \"x%2B1%2F4=-sqrt%2849%2F16%29\" Break up the \"plus/minus\" to form two equations.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B1%2F4=7%2F4\" or \"x%2B1%2F4=-7%2F4\" Take the square root of \"49%2F16\" to get \"7%2F4\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=-1%2F4%2B7%2F4\" or \"x=-1%2F4-7%2F4\" Subtract \"1%2F4\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x=3%2F2\" or \"x=-2\" Combine like terms.\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=3%2F2\" or \"x=-2\".\r
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\n" ); document.write( "\n" ); document.write( "Note: the order of the solutions does NOT matter.\r
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