document.write( "Question 129983: I am so very confused. This is from an on line course, Graph the function f(X)=-3^+X-5. At this point I have come up numerous answers \n" ); document.write( "

Algebra.Com's Answer #94963 by jim_thompson5910(35256) $\"\"$ $\"About$

You can put this solution on YOUR website!
I'm assuming you want to graph $\"f%28x%29=-3x%5E2%2Bx-5\"$ right?\r
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\n" ); document.write( "\n" ); document.write( "In order to graph $\"f%28x%29=-3x%5E2%2Bx-5\"$ , we need to plot some points. To do that, we need to plug in some x values to get some y values\r
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\n" ); document.write( "\n" ); document.write( "So let's find the first point:\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28x%29=-3x%5E2%2B1x-5\"$ Start with the given function\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-1%29=-3%28-1%29%5E2%2B1%28-1%29-5\"$ Plug in $\"x=-1\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-1%29=-3%2A1%2B1%2A-1-5\"$ Raise -1 to the 2nd power to get 1\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-1%29=-3%2B1%2A-1-5\"$ Multiply -3 and 1 to get -3\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-1%29=-3%2B-1-5\"$ Multiply 1 and -1 to get -1\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-1%29=-4-5\"$ Add -3 and -1 to get -4\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-1%29=-9\"$ Subtract 5 from -4 to get -9\r
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\n" ); document.write( "\n" ); document.write( "So when $\"x=-1\"$ , we have $\"y=-9\"$ \r
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\n" ); document.write( "\n" ); document.write( "So our 1st point is (-1,-9)\r
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\n" ); document.write( "\n" ); document.write( "-------------- Let's find another point --------------\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28x%29=-3x%5E2%2B1x-5\"$ Start with the given function\r
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\n" ); document.write( "\n" ); document.write( " $\"f%280%29=-3%280%29%5E2%2B1%280%29-5\"$ Plug in $\"x=0\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%280%29=-3%2A0%2B1%2A0-5\"$ Raise 0 to the 2nd power to get 0\r
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\n" ); document.write( "\n" ); document.write( " $\"f%280%29=0%2B1%2A0-5\"$ Multiply -3 and 0 to get 0\r
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\n" ); document.write( "\n" ); document.write( " $\"f%280%29=0%2B0-5\"$ Multiply 1 and 0 to get 0\r
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\n" ); document.write( "\n" ); document.write( " $\"f%280%29=0-5\"$ Add 0 and 0 to get 0\r
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\n" ); document.write( "\n" ); document.write( " $\"f%280%29=-5\"$ Subtract 5 from 0 to get -5\r
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\n" ); document.write( "\n" ); document.write( "So when $\"x=0\"$ , we have $\"y=-5\"$ \r
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\n" ); document.write( "\n" ); document.write( "So our 2nd point is (0,-5)\r
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\n" ); document.write( "\n" ); document.write( "-------------- Let's find another point --------------\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28x%29=-3x%5E2%2B1x-5\"$ Start with the given function\r
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\n" ); document.write( "\n" ); document.write( " $\"f%281%29=-3%281%29%5E2%2B1%281%29-5\"$ Plug in $\"x=1\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%281%29=-3%2A1%2B1%2A1-5\"$ Raise 1 to the 2nd power to get 1\r
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\n" ); document.write( "\n" ); document.write( " $\"f%281%29=-3%2B1%2A1-5\"$ Multiply -3 and 1 to get -3\r
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\n" ); document.write( "\n" ); document.write( " $\"f%281%29=-3%2B1-5\"$ Multiply 1 and 1 to get 1\r
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\n" ); document.write( "\n" ); document.write( " $\"f%281%29=-2-5\"$ Add -3 and 1 to get -2\r
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\n" ); document.write( "\n" ); document.write( " $\"f%281%29=-7\"$ Subtract 5 from -2 to get -7\r
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\n" ); document.write( "\n" ); document.write( "So when $\"x=1\"$ , we have $\"y=-7\"$ \r
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\n" ); document.write( "\n" ); document.write( "So our 3rd point is (1,-7)\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
 -1 -9
 0 -5
 1 -7\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 $\"y=-3x%5E2%2B1x-5\"$ (note: the more points you plot, the easier it is to draw the graph)\r
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