document.write( "Question 152928: Another graphing a function question! I can't figure the graphing part out.\r
\n" ); document.write( "\n" ); document.write( "Graph the function f(x)= -3x squared + x-5 \n" ); document.write( "

Algebra.Com's Answer #112379 by jim_thompson5910(35256) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "Jump to Table\r
\n" ); document.write( "\n" ); document.write( "Jump to Graph\r
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\n" ); document.write( "\n" ); document.write( "In order to graph $\"y=-3x%5E2%2Bx-5\"$ , we need to plot some points.\r
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\n" ); document.write( "\n" ); document.write( "Let's find y when $\"x=-2\"$ \r
\n" ); document.write( "\n" ); document.write( "(Note: you can start with any x-value):\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-3x%5E2%2Bx-5\"$ Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-3%28-2%29%5E2%2B-2-5\"$ Plug in $\"x=-2\"$ .\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-3%284%29-2-5\"$ Square $\"-2\"$ to get $\"4\"$ .\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-12-2-5\"$ Multiply $\"-3\"$ and $\"4\"$ to get $\"-12\"$ .\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-19\"$ Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So when $\"x=-2\"$ , then $\"y=-19\"$ .\r
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\n" ); document.write( "\n" ); document.write( "So we have the point

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\n" ); document.write( "\n" ); document.write( "Let's find y when $\"x=-1\"$ :\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-3x%5E2%2Bx-5\"$ Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-3%28-1%29%5E2%2B-1-5\"$ Plug in $\"x=-1\"$ .\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-3%281%29-1-5\"$ Square $\"-1\"$ to get $\"1\"$ .\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-3-1-5\"$ Multiply $\"-3\"$ and $\"1\"$ to get $\"-3\"$ .\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-9\"$ Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So when $\"x=-1\"$ , then $\"y=-9\"$ .\r
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\n" ); document.write( "\n" ); document.write( "So we have the point

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\n" ); document.write( "\n" ); document.write( "Let's find y when $\"x=0\"$ :\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-3x%5E2%2Bx-5\"$ Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-3%280%29%5E2%2B0-5\"$ Plug in $\"x=0\"$ .\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-3%280%29%2B0-5\"$ Square $\"0\"$ to get $\"0\"$ .\r
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\n" ); document.write( "\n" ); document.write( " $\"y=0%2B0-5\"$ Multiply $\"-3\"$ and $\"0\"$ to get $\"0\"$ .\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 when $\"x=0\"$ , then $\"y=-5\"$ .\r
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\n" ); document.write( "\n" ); document.write( "So we have the point

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\n" ); document.write( "\n" ); document.write( "Let's find y when $\"x=1\"$ :\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-3x%5E2%2Bx-5\"$ Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-3%281%29%5E2%2B1-5\"$ Plug in $\"x=1\"$ .\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-3%281%29%2B1-5\"$ Square $\"1\"$ to get $\"1\"$ .\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-3%2B1-5\"$ Multiply $\"-3\"$ and $\"1\"$ to get $\"-3\"$ .\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-7\"$ Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So when $\"x=1\"$ , then $\"y=-7\"$ .\r
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\n" ); document.write( "\n" ); document.write( "So we have the point

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\n" ); document.write( "\n" ); document.write( "Let's find y when $\"x=2\"$ :\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-3x%5E2%2Bx-5\"$ Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-3%282%29%5E2%2B2-5\"$ Plug in $\"x=2\"$ .\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-3%284%29%2B2-5\"$ Square $\"2\"$ to get $\"4\"$ .\r
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\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " $\"y=-12%2B2-5\"$ Multiply $\"-3\"$ and $\"4\"$ to get $\"-12\"$ .\r
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\n" ); document.write( "\n" ); document.write( " $\"y=-15\"$ Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So when $\"x=2\"$ , then $\"y=-15\"$ .\r
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\n" ); document.write( "\n" ); document.write( "So we have the point

Table of Values:

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document.write( "x y
-2 -19
-1 -9
0 -5
1 -7
2 -15\r\n" );
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Graph:

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\n" ); document.write( "\n" ); document.write( "Now draw a curve through all of the points to graph $\"y=-3x%5E2%2Bx-5\"$ :\r
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Graph of $\"y=-3x%5E2%2Bx-5\"$ \n" ); document.write( "

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