document.write( "Question 174319This question is from textbook algebra 1
\n" ); document.write( ": sketch a graph of all the (x,y)coordinates that satisfy the equation
\n" ); document.write( "y-x2=-1. What shape is the graph?
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Algebra.Com's Answer #129272 by jim_thompson5910(35256)\"\" \"About 
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\"y-x%5E2=-1\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=x%5E2-1\" Add \"x%5E2\" to both sides.\r
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Jump to Table\r
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\n" ); document.write( "\n" ); document.write( "In order to graph \"y=x%5E2-1\", we need to plot some points.\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%5E2-1\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-3%29%5E2-1\" Plug in \"x=-3\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=9-1\" Square \"-3\" to get \"9\".\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=-2\":\r
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\n" ); document.write( "\n" ); document.write( "\"y=x%5E2-1\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-2%29%5E2-1\" Plug in \"x=-2\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=4-1\" Square \"-2\" to get \"4\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=3\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So when \"x=-2\", then \"y=3\".\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%5E2-1\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-1%29%5E2-1\" Plug in \"x=-1\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=1-1\" Square \"-1\" to get \"1\".\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=0\":\r
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\n" ); document.write( "\n" ); document.write( "\"y=x%5E2-1\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%280%29%5E2-1\" Plug in \"x=0\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=0-1\" Square \"0\" to get \"0\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=-1\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So when \"x=0\", then \"y=-1\".\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%5E2-1\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%281%29%5E2-1\" Plug in \"x=1\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=1-1\" Square \"1\" to get \"1\".\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%5E2-1\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%282%29%5E2-1\" Plug in \"x=2\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=4-1\" Square \"2\" to get \"4\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=3\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So when \"x=2\", then \"y=3\".\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%5E2-1\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%283%29%5E2-1\" Plug in \"x=3\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=9-1\" Square \"3\" to get \"9\".\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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Jump to Top of Page\r
\n" ); document.write( "\n" ); document.write( "Now let's make a table of the values we just found.\r
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Table of Values:

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xy
-38
-23
-10
0-1
10
23
38
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\n" ); document.write( "\n" ); document.write( "Now let's plot the points:\r
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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%5E2-1\":\r
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\n" ); document.write( "\n" ); document.write( " Graph of \"y=x%5E2-1\" (which is also the graph of \"y-x%5E2=-1\")\r
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\n" ); document.write( "\n" ); document.write( "So the shape of \"y-x%5E2=-1\" is a parabola.
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