document.write( "Question 193063: i should find the vertex of the following: f(x) = x^2+8x+27\r
\n" ); document.write( "\n" ); document.write( "do i have to do it as follows?\r
\n" ); document.write( "\n" ); document.write( "x^2+8x+16-16+27\r
\n" ); document.write( "\n" ); document.write( "(x+4)^2+27\r
\n" ); document.write( "\n" ); document.write( "a(x-(-8)^2+27\r
\n" ); document.write( "\n" ); document.write( "vertex is (-8, 27)? somehow this seems very wrong to me...
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Algebra.Com's Answer #144901 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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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%2B8x%2B27\", we can see that \"a=1\", \"b=8\", and \"c=27\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-%288%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=%28-8%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%2B8x%2B27\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-4%29%5E2%2B8%28-4%29%2B27\" Plug in \"x=-4\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=1%2816%29%2B8%28-4%29%2B27\" Square \"-4\" to get \"16\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=16%2B8%28-4%29%2B27\" Multiply \"1\" and \"16\" to get \"16\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=16-32%2B27\" Multiply \"8\" and \"-4\" to get \"-32\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=11\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So the y-coordinate of the vertex is \"y=11\".\r
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\n" ); document.write( "\n" ); document.write( "So the vertex is .
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