document.write( "Question 316651: How do you graph the equation: \"x%5E2-8x%2B7\"?
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Algebra.Com's Answer #226578 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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Jump to Table\r
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\n" ); document.write( "\n" ); document.write( "In order to graph \"y=x%5E2-8x%2B7\", we need to plot some points.\r
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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=x%5E2-8x%2B7\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%280%29%5E2-8%280%29%2B7\" Plug in \"x=0\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=1%280%29-8%280%29%2B7\" Square \"0\" to get \"0\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=0-8%280%29%2B7\" Multiply \"1\" and \"0\" to get \"0\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=0%2B0%2B7\" Multiply \"-8\" and \"0\" to get \"0\".\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=0\", then \"y=7\".\r
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\n" ); document.write( "\n" ); document.write( "So we have the point .\r
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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=x%5E2-8x%2B7\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%281%29%5E2-8%281%29%2B7\" Plug in \"x=1\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=1%281%29-8%281%29%2B7\" Square \"1\" to get \"1\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=1-8%281%29%2B7\" Multiply \"1\" and \"1\" to get \"1\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=1-8%2B7\" Multiply \"-8\" and \"1\" to get \"-8\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=0\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So when \"x=1\", then \"y=0\".\r
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\n" ); document.write( "\n" ); document.write( "So we have the point .\r
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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=x%5E2-8x%2B7\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%282%29%5E2-8%282%29%2B7\" Plug in \"x=2\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=1%284%29-8%282%29%2B7\" Square \"2\" to get \"4\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=4-8%282%29%2B7\" Multiply \"1\" and \"4\" to get \"4\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=4-16%2B7\" Multiply \"-8\" and \"2\" to get \"-16\".\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=2\", then \"y=-5\".\r
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\n" ); document.write( "\n" ); document.write( "So we have the point .\r
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\n" ); document.write( "\n" ); document.write( "Let's find y when \"x=3\":\r
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\n" ); document.write( "\n" ); document.write( "\"y=x%5E2-8x%2B7\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%283%29%5E2-8%283%29%2B7\" Plug in \"x=3\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=1%289%29-8%283%29%2B7\" Square \"3\" to get \"9\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=9-8%283%29%2B7\" Multiply \"1\" and \"9\" to get \"9\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=9-24%2B7\" Multiply \"-8\" and \"3\" to get \"-24\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=-8\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So when \"x=3\", then \"y=-8\".\r
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\n" ); document.write( "\n" ); document.write( "So we have the point .\r
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\n" ); document.write( "\n" ); document.write( "Let's find y when \"x=4\":\r
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\n" ); document.write( "\n" ); document.write( "\"y=x%5E2-8x%2B7\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%284%29%5E2-8%284%29%2B7\" Plug in \"x=4\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=1%2816%29-8%284%29%2B7\" Square \"4\" to get \"16\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=16-8%284%29%2B7\" Multiply \"1\" and \"16\" to get \"16\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=16-32%2B7\" Multiply \"-8\" and \"4\" to get \"-32\".\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=4\", then \"y=-9\".\r
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\n" ); document.write( "\n" ); document.write( "So we have the point .\r
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\n" ); document.write( "\n" ); document.write( "Let's find y when \"x=5\":\r
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\n" ); document.write( "\n" ); document.write( "\"y=x%5E2-8x%2B7\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%285%29%5E2-8%285%29%2B7\" Plug in \"x=5\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=1%2825%29-8%285%29%2B7\" Square \"5\" to get \"25\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=25-8%285%29%2B7\" Multiply \"1\" and \"25\" to get \"25\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=25-40%2B7\" Multiply \"-8\" and \"5\" to get \"-40\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=-8\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So when \"x=5\", then \"y=-8\".\r
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\n" ); document.write( "\n" ); document.write( "So we have the point .\r
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\n" ); document.write( "\n" ); document.write( "Let's find y when \"x=6\":\r
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\n" ); document.write( "\n" ); document.write( "\"y=x%5E2-8x%2B7\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%286%29%5E2-8%286%29%2B7\" Plug in \"x=6\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=1%2836%29-8%286%29%2B7\" Square \"6\" to get \"36\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=36-8%286%29%2B7\" Multiply \"1\" and \"36\" to get \"36\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=36-48%2B7\" Multiply \"-8\" and \"6\" to get \"-48\".\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=6\", then \"y=-5\".\r
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\n" ); document.write( "\n" ); document.write( "So we have the point .\r
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\n" ); document.write( "\n" ); document.write( "Let's find y when \"x=7\":\r
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\n" ); document.write( "\n" ); document.write( "\"y=x%5E2-8x%2B7\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%287%29%5E2-8%287%29%2B7\" Plug in \"x=7\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=1%2849%29-8%287%29%2B7\" Square \"7\" to get \"49\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=49-8%287%29%2B7\" Multiply \"1\" and \"49\" to get \"49\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=49-56%2B7\" Multiply \"-8\" and \"7\" to get \"-56\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=0\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So when \"x=7\", then \"y=0\".\r
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\n" ); document.write( "\n" ); document.write( "So we have the point .\r
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\n" ); document.write( "\n" ); document.write( "Let's find y when \"x=8\":\r
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\n" ); document.write( "\n" ); document.write( "\"y=x%5E2-8x%2B7\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%288%29%5E2-8%288%29%2B7\" Plug in \"x=8\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=1%2864%29-8%288%29%2B7\" Square \"8\" to get \"64\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=64-8%288%29%2B7\" Multiply \"1\" and \"64\" to get \"64\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=64-64%2B7\" Multiply \"-8\" and \"8\" to get \"-64\".\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=8\", then \"y=7\".\r
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Jump to Top of Page\r
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Table of Values:

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xy
07
10
2-5
3-8
4-9
5-8
6-5
70
87
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Jump to Top of Page\r
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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=x%5E2-8x%2B7\":\r
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\n" ); document.write( "\n" ); document.write( " Graph of \"y=x%5E2-8x%2B7\"
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