document.write( "Question 118382: Sketch the graphs, using the given roots to determine the function and the turning point.\r
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Algebra.Com's Answer #86501 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"x=-8\" or \"x=-6\" Start with the given roots\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B8=0\" or \"x%2B6=0\" Add 8 to both sides for the first equation. Add 6 to both sides for the second equation. \r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B8%29%28x%2B6%29=0\" Now use the zero product property in reverse. Remember the zero product property says that if \"A%2AB=0\" then \"A=0\" or \"B=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B14x%2B48=0\" Now foil. note: Let me know if you need help with foiling.\r
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\n" ); document.write( "\n" ); document.write( "Now to find the turning point, we need to find the x-coordinate of the turning point. To do that, simply use this formula: \"x=-b%2F2a\"\r
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\n" ); document.write( "\n" ); document.write( "So from \"f%28x%29=x%5E2%2B14x%2B48\" we can see that \"a=1\" and \"b=14\". \r
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\n" ); document.write( "\n" ); document.write( "\"x=-14%2F2%281%29\" Plug \"a=1\" and \"b=-2\" into the formula. \r
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\n" ); document.write( "\n" ); document.write( "\"x=-14%2F2\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"x=-7\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "So the x-coordinate of the turning point is \"x=-7\" \r
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\n" ); document.write( "\n" ); document.write( "Now we have to evaluate \"f%28-7%29\" to determine the y-coordinate of the turning point.\r
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\n" ); document.write( "\n" ); document.write( "\"f%28x%29=x%5E2%2B14x%2B48\" Start with the given function.\r
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\n" ); document.write( "\n" ); document.write( "\"f%28-7%29=%28-7%29%5E2%2B14%28-7%29%2B48\" Plug in \"x=-7\". In other words, replace each x with -7.\r
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\n" ); document.write( "\n" ); document.write( "\"f%28-7%29=%2849%29%2B14%28-7%29%2B48\" Evaluate \"%28-7%29%5E2\" to get 49.\r
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\n" ); document.write( "\n" ); document.write( "\"f%28-7%29=%2849%29%2B-98%2B48\" Multiply 14 and -7 to get -98\r
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\n" ); document.write( "\n" ); document.write( "\"f%28-7%29=-1\" Now combine like terms\r
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\n" ); document.write( "\n" ); document.write( "So the turning point is at (-7,-1)\r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph \"f%28x%29=x%5E2%2B14x%2B48\", we can see that the roots are\"x=-8\" and \"x=-6\". We can also see that the turning point is (-7,-1). So this visually verifies our answer.\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C0%2C+x%5E2%2B14x%2B48%29+\"\r
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