document.write( "Question 241751: can you figure out the answer to this equation, 3x^2+14x+94 using the completing the square method? \n" ); document.write( "
Algebra.Com's Answer #177053 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"3x%5E2%2B14x%2B94\" Start with the given expression.\r
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\n" ); document.write( "\n" ); document.write( "\"3%28x%5E2%2B%2814%2F3%29x%2B94%2F3%29\" Factor out the \"x%5E2\" coefficient \"3\". 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 \"14%2F3\" to get \"7%2F3\". In other words, \"%281%2F2%29%2814%2F3%29=7%2F3\".\r
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\n" ); document.write( "\n" ); document.write( "Now square \"7%2F3\" to get \"49%2F9\". In other words, \"%287%2F3%29%5E2=%287%2F3%29%287%2F3%29=49%2F9\"\r
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\n" ); document.write( "\n" ); document.write( "\"3%28x%5E2%2B%2814%2F3%29x%2Bhighlight%2849%2F9-49%2F9%29%2B94%2F3%29\" Now add and subtract \"49%2F9\" inside the parenthesis. Make sure to place this after the \"x\" term. Notice how \"49%2F9-49%2F9=0\". So the expression is not changed.\r
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\n" ); document.write( "\n" ); document.write( "\"3%28%28x%5E2%2B%2814%2F3%29x%2B49%2F9%29-49%2F9%2B94%2F3%29\" Group the first three terms.\r
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\n" ); document.write( "\n" ); document.write( "\"3%28%28x%2B7%2F3%29%5E2-49%2F9%2B94%2F3%29\" Factor \"x%5E2%2B%2814%2F3%29x%2B49%2F9\" to get \"%28x%2B7%2F3%29%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "\"3%28%28x%2B7%2F3%29%5E2%2B233%2F9%29\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"3%28x%2B7%2F3%29%5E2%2B3%28233%2F9%29\" Distribute.\r
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\n" ); document.write( "\n" ); document.write( "\"3%28x%2B7%2F3%29%5E2%2B233%2F3\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "So after completing the square, \"3x%5E2%2B14x%2B94\" transforms to \"3%28x%2B7%2F3%29%5E2%2B233%2F3\". So \"3x%5E2%2B14x%2B94=3%28x%2B7%2F3%29%5E2%2B233%2F3\".\r
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\n" ); document.write( "\n" ); document.write( "So \"3x%5E2%2B14x%2B94=0\" is equivalent to \"3%28x%2B7%2F3%29%5E2%2B233%2F3=0\".\r
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\n" ); document.write( "\n" ); document.write( "So to solve \"3x%5E2%2B14x%2B94=0\", we can solve \"3%28x%2B7%2F3%29%5E2%2B233%2F3=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"3%28x%2B7%2F3%29%5E2%2B233%2F3=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"3%28x%2B7%2F3%29%5E2=0-233%2F3\"Subtract \"233%2F3\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"3%28x%2B7%2F3%29%5E2=-233%2F3\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B7%2F3%29%5E2=%28-233%2F3%29%2F%283%29\" Divide both sides by \"3\".\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B7%2F3%29%5E2=-233%2F9\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B7%2F3=%22%22%2B-sqrt%28-233%2F9%29\" Take the square root of both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B7%2F3=sqrt%28-233%2F9%29\" or \"x%2B7%2F3=-sqrt%28-233%2F9%29\" Break up the \"plus/minus\" to form two equations.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B7%2F3=%28i%2Asqrt%28233%29%29%2F3\" or \"x%2B7%2F3=-%28i%2Asqrt%28233%29%29%2F3\" Simplify the square root.\r
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\n" ); document.write( "\n" ); document.write( "\"x=-7%2F3%2B%28i%2Asqrt%28233%29%29%2F3\" or \"x=-7%2F3-%28i%2Asqrt%28233%29%29%2F3\" Subtract \"7%2F3\" from both sides.\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=-7%2F3%2B%28i%2Asqrt%28233%29%29%2F3\" or \"x=-7%2F3-%28i%2Asqrt%28233%29%29%2F3\".\r
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