document.write( "Question 117549: How do you put 2n^2-4n-6=0 in to a graph or table . Round to the nearst tenth \n" ); document.write( "

Algebra.Com's Answer #85542 by jim_thompson5910(35256) $\"\"$ $\"About$

You can put this solution on YOUR website!
In order to make a table, just plug in some n values. So I'm going to start at n=-5\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28x%29=2n%5E2-4n-6\"$ Start with the given function.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-5%29=2%28-5%29%5E2-4%28-5%29-6\"$ Plug in $\"n=-5\"$ . In other words, replace each n with -5.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-5%29=2%2825%29-4%28-5%29-6\"$ Evaluate $\"%28-5%29%5E2\"$ to get 25.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-5%29=%2B50-4%28-5%29-6\"$ Multiply 2 and 25 to get 50\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-5%29=%2B50%2B20-6\"$ Multiply -4 and -5 to get 20\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-5%29=64\"$ Now combine like terms\r
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\n" ); document.write( "\n" ); document.write( "-----------Now let's evaluate another value---------\r
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\n" ); document.write( "\n" ); document.write( "Let's evaluate $\"f%28-4%29\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%28x%29=2n%5E2-4n-6\"$ Start with the given function.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-4%29=2%28-4%29%5E2-4%28-4%29-6\"$ Plug in $\"n=-4\"$ . In other words, replace each n with -4.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-4%29=2%2816%29-4%28-4%29-6\"$ Evaluate $\"%28-4%29%5E2\"$ to get 16.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-4%29=%2B32-4%28-4%29-6\"$ Multiply 2 and 16 to get 32\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-4%29=%2B32%2B16-6\"$ Multiply -4 and -4 to get 16\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-4%29=42\"$ Now combine like terms\r
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\n" ); document.write( "\n" ); document.write( "-----------Now let's evaluate another value---------\r
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\n" ); document.write( "\n" ); document.write( "Let's evaluate $\"f%28-3%29\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%28x%29=2n%5E2-4n-6\"$ Start with the given function.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-3%29=2%28-3%29%5E2-4%28-3%29-6\"$ Plug in $\"n=-3\"$ . In other words, replace each n with -3.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-3%29=2%289%29-4%28-3%29-6\"$ Evaluate $\"%28-3%29%5E2\"$ to get 9.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-3%29=%2B18-4%28-3%29-6\"$ Multiply 2 and 9 to get 18\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-3%29=%2B18%2B12-6\"$ Multiply -4 and -3 to get 12\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-3%29=24\"$ Now combine like terms\r
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\n" ); document.write( "\n" ); document.write( "-----------Now let's evaluate another value---------\r
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\n" ); document.write( "\n" ); document.write( "Let's evaluate $\"f%28-2%29\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%28x%29=2n%5E2-4n-6\"$ Start with the given function.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-2%29=2%28-2%29%5E2-4%28-2%29-6\"$ Plug in $\"n=-2\"$ . In other words, replace each n with -2.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-2%29=2%284%29-4%28-2%29-6\"$ Evaluate $\"%28-2%29%5E2\"$ to get 4.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-2%29=%2B8-4%28-2%29-6\"$ Multiply 2 and 4 to get 8\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-2%29=%2B8%2B8-6\"$ Multiply -4 and -2 to get 8\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-2%29=10\"$ Now combine like terms\r
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\n" ); document.write( "\n" ); document.write( "-----------Now let's evaluate another value---------\r
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\n" ); document.write( "\n" ); document.write( "Let's evaluate $\"f%28-1%29\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%28x%29=2n%5E2-4n-6\"$ Start with the given function.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-1%29=2%28-1%29%5E2-4%28-1%29-6\"$ Plug in $\"n=-1\"$ . In other words, replace each n with -1.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-1%29=2%281%29-4%28-1%29-6\"$ Evaluate $\"%28-1%29%5E2\"$ to get 1.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-1%29=%2B2-4%28-1%29-6\"$ Multiply 2 and 1 to get 2\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-1%29=%2B2%2B4-6\"$ Multiply -4 and -1 to get 4\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-1%29=0\"$ Now combine like terms\r
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\n" ); document.write( "\n" ); document.write( "-----------Now let's evaluate another value---------\r
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\n" ); document.write( "\n" ); document.write( "Let's evaluate $\"f%280%29\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%28x%29=2n%5E2-4n-6\"$ Start with the given function.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%280%29=2%280%29%5E2-4%280%29-6\"$ Plug in $\"n=0\"$ . In other words, replace each n with 0.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%280%29=2%280%29-4%280%29-6\"$ Evaluate $\"%280%29%5E2\"$ to get 0.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%280%29=%2B0-4%280%29-6\"$ Multiply 2 and 0 to get 0\r
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\n" ); document.write( "\n" ); document.write( " $\"f%280%29=%2B0%2B0-6\"$ Multiply -4 and 0 to get 0\r
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\n" ); document.write( "\n" ); document.write( " $\"f%280%29=-6\"$ Now combine like terms\r
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\n" ); document.write( "\n" ); document.write( "-----------Now let's evaluate another value---------\r
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\n" ); document.write( "\n" ); document.write( "Let's evaluate $\"f%281%29\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%28x%29=2n%5E2-4n-6\"$ Start with the given function.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%281%29=2%281%29%5E2-4%281%29-6\"$ Plug in $\"n=1\"$ . In other words, replace each n with 1.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%281%29=2%281%29-4%281%29-6\"$ Evaluate $\"%281%29%5E2\"$ to get 1.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%281%29=%2B2-4%281%29-6\"$ Multiply 2 and 1 to get 2\r
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\n" ); document.write( "\n" ); document.write( " $\"f%281%29=%2B2-4-6\"$ Multiply -4 and 1 to get -4\r
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\n" ); document.write( "\n" ); document.write( " $\"f%281%29=-8\"$ Now combine like terms\r
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\n" ); document.write( "\n" ); document.write( "-----------Now let's evaluate another value---------\r
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\n" ); document.write( "\n" ); document.write( "Let's evaluate $\"f%282%29\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%28x%29=2n%5E2-4n-6\"$ Start with the given function.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%282%29=2%282%29%5E2-4%282%29-6\"$ Plug in $\"n=2\"$ . In other words, replace each n with 2.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%282%29=2%284%29-4%282%29-6\"$ Evaluate $\"%282%29%5E2\"$ to get 4.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%282%29=%2B8-4%282%29-6\"$ Multiply 2 and 4 to get 8\r
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\n" ); document.write( "\n" ); document.write( " $\"f%282%29=%2B8-8-6\"$ Multiply -4 and 2 to get -8\r
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\n" ); document.write( "\n" ); document.write( " $\"f%282%29=-6\"$ Now combine like terms\r
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\n" ); document.write( "\n" ); document.write( "-----------Now let's evaluate another value---------\r
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\n" ); document.write( "\n" ); document.write( "Let's evaluate $\"f%283%29\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%28x%29=2n%5E2-4n-6\"$ Start with the given function.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%283%29=2%283%29%5E2-4%283%29-6\"$ Plug in $\"n=3\"$ . In other words, replace each n with 3.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%283%29=2%289%29-4%283%29-6\"$ Evaluate $\"%283%29%5E2\"$ to get 9.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%283%29=%2B18-4%283%29-6\"$ Multiply 2 and 9 to get 18\r
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\n" ); document.write( "\n" ); document.write( " $\"f%283%29=%2B18-12-6\"$ Multiply -4 and 3 to get -12\r
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\n" ); document.write( "\n" ); document.write( " $\"f%283%29=0\"$ Now combine like terms\r
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\n" ); document.write( "\n" ); document.write( "-----------Now let's evaluate another value---------\r
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\n" ); document.write( "\n" ); document.write( "Let's evaluate $\"f%284%29\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%28x%29=2n%5E2-4n-6\"$ Start with the given function.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%284%29=2%284%29%5E2-4%284%29-6\"$ Plug in $\"n=4\"$ . In other words, replace each n with 4.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%284%29=2%2816%29-4%284%29-6\"$ Evaluate $\"%284%29%5E2\"$ to get 16.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%284%29=%2B32-4%284%29-6\"$ Multiply 2 and 16 to get 32\r
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\n" ); document.write( "\n" ); document.write( " $\"f%284%29=%2B32-16-6\"$ Multiply -4 and 4 to get -16\r
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\n" ); document.write( "\n" ); document.write( " $\"f%284%29=10\"$ Now combine like terms\r
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\n" ); document.write( "\n" ); document.write( "-----------Now let's evaluate another value---------\r
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\n" ); document.write( "\n" ); document.write( "Let's evaluate $\"f%285%29\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%28x%29=2n%5E2-4n-6\"$ Start with the given function.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%285%29=2%285%29%5E2-4%285%29-6\"$ Plug in $\"n=5\"$ . In other words, replace each n with 5.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%285%29=2%2825%29-4%285%29-6\"$ Evaluate $\"%285%29%5E2\"$ to get 25.\r
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\n" ); document.write( "\n" ); document.write( " $\"f%285%29=%2B50-4%285%29-6\"$ Multiply 2 and 25 to get 50\r
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\n" ); document.write( "\n" ); document.write( " $\"f%285%29=%2B50-20-6\"$ Multiply -4 and 5 to get -20\r
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\n" ); document.write( "\n" ); document.write( " $\"f%285%29=24\"$ Now combine like terms\r
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\n" ); document.write( "\n" ); document.write( "Now lets make a table of the values we have calculated\r
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document.write( " x y
 -5 64
 -4 42
 -3 24
 -2 10
 -1 0
 0 -6
 1 -8
 2 -6
 3 0
 4 10
 5 24\r\n" );
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Now plot the points\r
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\n" ); document.write( "\n" ); document.write( "Now connect the points to graph $\"y=2n%5E2-4n-6\"$ (just replace n with x) (note: the more points you plot, the easier it is to draw the graph)\r
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