document.write( "Question 130959: I wanted to know how to graph the equation of xy=4.
\n" ); document.write( "I need to find the center and the equations of the asymptotes.
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Algebra.Com's Answer #95564 by jim_thompson5910(35256) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"xy=4\"$ Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( " $\"y=4%2Fx\"$ Divide both sides by x to isolate y\r
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\n" ); document.write( "\n" ); document.write( "In order to graph $\"f%28x%29=4%2Fx\"$ , 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( " $\"f%28x%29=4%2Fx\"$ Start with the given function\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-4%29=4%2F%28-4%29\"$ Plug in $\"x=-4\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-4%29=-1\"$ Divide -4 into 4 to get -1\r
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\n" ); document.write( "\n" ); document.write( "So when $\"x=-4\"$ , we have $\"y=-1\"$ \r
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\n" ); document.write( "\n" ); document.write( "So our 1st point is (-4,-1)\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( " $\"f%28x%29=4%2Fx\"$ Start with the given function\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-3%29=4%2F%28-3%29\"$ Plug in $\"x=-3\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-3%29=-1.3333\"$ Divide -3 into 4 to get -1.33333333333333\r
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\n" ); document.write( "\n" ); document.write( "So when $\"x=-3\"$ , we have $\"y=-1.33333333333333\"$ \r
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\n" ); document.write( "\n" ); document.write( "So our 2nd point is (-3,-1.33333333333333)\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( " $\"f%28x%29=4%2Fx\"$ Start with the given function\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-2%29=4%2F%28-2%29\"$ Plug in $\"x=-2\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-2%29=-2\"$ Divide -2 into 4 to get -2\r
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\n" ); document.write( "\n" ); document.write( "So when $\"x=-2\"$ , we have $\"y=-2\"$ \r
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\n" ); document.write( "\n" ); document.write( "So our 3rd point is (-2,-2)\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( " $\"f%28x%29=4%2Fx\"$ Start with the given function\r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-1%29=4%2F%28-1%29\"$ Plug in $\"x=-1\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%28-1%29=-4\"$ Divide -1 into 4 to get -4\r
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\n" ); document.write( "\n" ); document.write( "So when $\"x=-1\"$ , we have $\"y=-4\"$ \r
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\n" ); document.write( "\n" ); document.write( "So our 4th point is (-1,-4)\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( " $\"f%28x%29=4%2Fx\"$ Start with the given function\r
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\n" ); document.write( "\n" ); document.write( " $\"f%281%29=4%2F%281%29\"$ Plug in $\"x=1\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%281%29=4\"$ Divide 1 into 4 to get 4\r
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\n" ); document.write( "\n" ); document.write( "So when $\"x=1\"$ , we have $\"y=4\"$ \r
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\n" ); document.write( "\n" ); document.write( "So our 5th point is (1,4)\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( " $\"f%28x%29=4%2Fx\"$ Start with the given function\r
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\n" ); document.write( "\n" ); document.write( " $\"f%282%29=4%2F%282%29\"$ Plug in $\"x=2\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%282%29=2\"$ Divide 2 into 4 to get 2\r
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\n" ); document.write( "\n" ); document.write( "So when $\"x=2\"$ , we have $\"y=2\"$ \r
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\n" ); document.write( "\n" ); document.write( "So our 6th point is (2,2)\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( " $\"f%28x%29=4%2Fx\"$ Start with the given function\r
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\n" ); document.write( "\n" ); document.write( " $\"f%283%29=4%2F%283%29\"$ Plug in $\"x=3\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%283%29=1.3333\"$ Divide 3 into 4 to get 1.33333333333333\r
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\n" ); document.write( "\n" ); document.write( "So when $\"x=3\"$ , we have $\"y=1.33333333333333\"$ \r
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\n" ); document.write( "\n" ); document.write( "So our 7th point is (3,1.33333333333333)\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( " $\"f%28x%29=4%2Fx\"$ Start with the given function\r
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\n" ); document.write( "\n" ); document.write( " $\"f%284%29=4%2F%284%29\"$ Plug in $\"x=4\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"f%284%29=1\"$ Divide 4 into 4 to get 1\r
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\n" ); document.write( "\n" ); document.write( "So when $\"x=4\"$ , we have $\"y=1\"$ \r
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\n" ); document.write( "\n" ); document.write( "So our 8th point is (4,1)\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
 -4 -1
 -3 -1.33333333333333
 -2 -2
 -1 -4
 1 4
 2 2
 3 1.33333333333333
 4 1\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 $\"y=4%2Fx\"$ (note: the more points you plot, the easier it is to draw the graph)\r
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\n" ); document.write( "\n" ); document.write( "From this graph, we can see that the center is (0,0), the vertical asymptote is $\"x=0\"$ and the horizontal asymptote is $\"y=0\"$ \n" ); document.write( "

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