document.write( "Question 215000: Determine the vertex of the function by completing the square.
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\n" ); document.write( "\n" ); document.write( "An explanation of how to go about completing the square would be very much appreciated! Thanks!\r
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Algebra.Com's Answer #162462 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"-18x%5E2-177x-190\" Start with the given expression.\r
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\n" ); document.write( "\n" ); document.write( "\"-18%28x%5E2%2B%2859%2F6%29x%2B95%2F9%29\" Factor out the \"x%5E2\" coefficient \"-18\". 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 \"59%2F6\" to get \"59%2F12\". In other words, \"%281%2F2%29%2859%2F6%29=59%2F12\".\r
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\n" ); document.write( "\n" ); document.write( "Now square \"59%2F12\" to get \"3481%2F144\". In other words, \"%2859%2F12%29%5E2=%2859%2F12%29%2859%2F12%29=3481%2F144\"\r
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\n" ); document.write( "\n" ); document.write( "\"-18%28x%5E2%2B%2859%2F6%29x%2Bhighlight%283481%2F144-3481%2F144%29%2B95%2F9%29\" Now add and subtract \"3481%2F144\" inside the parenthesis. Make sure to place this after the \"x\" term. Notice how \"3481%2F144-3481%2F144=0\". So the expression is not changed.\r
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\n" ); document.write( "\n" ); document.write( "\"-18%28%28x%5E2%2B%2859%2F6%29x%2B3481%2F144%29-3481%2F144%2B95%2F9%29\" Group the first three terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-18%28%28x%2B59%2F12%29%5E2-3481%2F144%2B95%2F9%29\" Factor \"x%5E2%2B%2859%2F6%29x%2B3481%2F144\" to get \"%28x%2B59%2F12%29%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "\"-18%28%28x%2B59%2F12%29%5E2-1961%2F144%29\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-18%28x%2B59%2F12%29%5E2-18%28-1961%2F144%29\" Distribute.\r
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\n" ); document.write( "\n" ); document.write( "\"-18%28x%2B59%2F12%29%5E2%2B1961%2F8\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "So after completing the square, \"-18x%5E2-177x-190\" transforms to \"-18%28x%2B59%2F12%29%5E2%2B1961%2F8\". So \"-18x%5E2-177x-190=-18%28x%2B59%2F12%29%5E2%2B1961%2F8\".\r
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\n" ); document.write( "\n" ); document.write( "So \"-18x%5E2-177x-190=0\" is equivalent to \"-18%28x%2B59%2F12%29%5E2%2B1961%2F8=0\".\r
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\n" ); document.write( "\n" ); document.write( "So \"y=-18x%5E2-177x-190\" is equivalent to \"y=-18%28x%2B59%2F12%29%5E2%2B1961%2F8\".\r
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\n" ); document.write( "\n" ); document.write( "So the equation \"y=-18%28x%2B59%2F12%29%5E2%2B1961%2F8\" is now in vertex form \"y=a%28x-h%29%5E2%2Bk\" where \"a=-18\", \"h=-59%2F12\", and \"k=1961%2F8\"\r
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\n" ); document.write( "\n" ); document.write( "Remember, the vertex of \"y=a%28x-h%29%5E2%2Bk\" is (h,k).\r
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\n" ); document.write( "\n" ); document.write( "So the vertex of \"y=-18%28x%2B59%2F12%29%5E2%2B1961%2F8\" is since \"h=-59%2F12\" and \"k=1961%2F8\"
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