document.write( "Question 207796: Identify the vertex and line of symmetry for y=x^2-8x+11 \n" ); document.write( "
Algebra.Com's Answer #157175 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "In order to find the vertex, we first need to find the x-coordinate of the vertex.\r
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\n" ); document.write( "\n" ); document.write( "To find the x-coordinate of the vertex, use this formula: \"x=%28-b%29%2F%282a%29\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-b%29%2F%282a%29\" Start with the given formula.\r
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\n" ); document.write( "\n" ); document.write( "From \"y=x%5E2-8x%2B11\", we can see that \"a=1\", \"b=-8\", and \"c=11\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-%28-8%29%29%2F%282%281%29%29\" Plug in \"a=1\" and \"b=-8\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=%288%29%2F%282%281%29%29\" Negate \"-8\" to get \"8\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=%288%29%2F%282%29\" Multiply 2 and \"1\" to get \"2\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=4\" Divide.\r
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\n" ); document.write( "\n" ); document.write( "So the x-coordinate of the vertex is \"x=4\". Note: this means that the axis of symmetry is also \"x=4\".\r
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\n" ); document.write( "\n" ); document.write( "Now that we know the x-coordinate of the vertex, we can use it to find the y-coordinate of the vertex.\r
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\n" ); document.write( "\n" ); document.write( "\"y=x%5E2-8x%2B11\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%284%29%5E2-8%284%29%2B11\" Plug in \"x=4\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=1%2816%29-8%284%29%2B11\" Square \"4\" to get \"16\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=16-8%284%29%2B11\" Multiply \"1\" and \"16\" to get \"16\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=16-32%2B11\" Multiply \"-8\" and \"4\" to get \"-32\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=-5\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So the y-coordinate of the vertex is \"y=-5\".\r
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\n" ); document.write( "\n" ); document.write( "So the vertex is .
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