document.write( "Question 92244: Solve the system by graphing.
\n" ); document.write( " x – 2y = 8
\n" ); document.write( " x + y = –1
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Algebra.Com's Answer #67089 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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Solved by pluggable solver: Solve the System of Equations by Graphing

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\n" ); document.write( " Start with the given system of equations:
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\n" ); document.write( " \"1x-2y=8\"
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\n" ); document.write( " \"1x%2By=-1\"
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\n" ); document.write( " In order to graph these equations, we need to solve for y for each equation.
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\n" ); document.write( " So let's solve for y on the first equation
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\n" ); document.write( " \"1x-2y=8\" Start with the given equation
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\n" ); document.write( " \"-2y=8-x\" Subtract \"+x\" from both sides
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\n" ); document.write( " \"-2y=-x%2B8\" Rearrange the equation
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\n" ); document.write( " \"y=%28-x%2B8%29%2F%28-2%29\" Divide both sides by \"-2\"
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\n" ); document.write( " \"y=%28-1%2F-2%29x%2B%288%29%2F%28-2%29\" Break up the fraction
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\n" ); document.write( " \"y=%281%2F2%29x-4\" Reduce
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\n" ); document.write( " Now lets graph \"y=%281%2F2%29x-4\" (note: if you need help with graphing, check out this solver)
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\n" ); document.write( " \"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+%281%2F2%29x-4%29+\" Graph of \"y=%281%2F2%29x-4\"
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\n" ); document.write( " So let's solve for y on the second equation
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\n" ); document.write( " \"1x%2By=-1\" Start with the given equation
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\n" ); document.write( " \"1y=-1-x\" Subtract \"+x\" from both sides
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\n" ); document.write( " \"1y=-x-1\" Rearrange the equation
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\n" ); document.write( " \"y=%28-x-1%29%2F%281%29\" Divide both sides by \"1\"
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\n" ); document.write( " \"y=%28-1%2F1%29x%2B%28-1%29%2F%281%29\" Break up the fraction
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\n" ); document.write( " \"y=-x-1\" Reduce
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\n" ); document.write( " Now lets add the graph of \"y=-x-1\" to our first plot to get:
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\n" ); document.write( " \"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+%281%2F2%29x-4%2C-x-1%29+\" Graph of \"y=%281%2F2%29x-4\"(red) and \"y=-x-1\"(green)
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\n" ); document.write( " From the graph, we can see that the two lines intersect at the point (\"2\",\"-3\") (note: you might have to adjust the window to see the intersection)
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