document.write( "Question 684259: solve the linear system by graphing
\n" ); document.write( "2x+y=-8 and -x+y=4 I know they intersect at -4. Is it 0 and -4 or -4 and 0
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Algebra.Com's Answer #424003 by MathLover1(20849)\"\" \"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( " \"2x%2By=-8\"
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\n" ); document.write( " \"-x%2By=4\"
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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( " \"2x%2By=-8\" Start with the given equation
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\n" ); document.write( " \"1y=-8-2x\" Subtract \"2+x\" from both sides
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\n" ); document.write( " \"1y=-2x-8\" Rearrange the equation
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\n" ); document.write( " \"y=%28-2x-8%29%2F%281%29\" Divide both sides by \"1\"
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\n" ); document.write( " \"y=%28-2%2F1%29x%2B%28-8%29%2F%281%29\" Break up the fraction
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\n" ); document.write( " \"y=-2x-8\" Reduce
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\n" ); document.write( " Now lets graph \"y=-2x-8\" (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+-2x-8%29+\" Graph of \"y=-2x-8\"
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\n" ); document.write( " So let's solve for y on the second equation
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\n" ); document.write( " \"-x%2By=4\" Start with the given equation
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\n" ); document.write( " \"1y=4%2Bx\" Add \"+x\" to both sides
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\n" ); document.write( " \"1y=%2Bx%2B4\" Rearrange the equation
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\n" ); document.write( " \"y=%28%2Bx%2B4%29%2F%281%29\" Divide both sides by \"1\"
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\n" ); document.write( " \"y=%28%2B1%2F1%29x%2B%284%29%2F%281%29\" Break up the fraction
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\n" ); document.write( " \"y=x%2B4\" Reduce
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\n" ); document.write( " Now lets add the graph of \"y=x%2B4\" 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+-2x-8%2Cx%2B4%29+\" Graph of \"y=-2x-8\"(red) and \"y=x%2B4\"(green)
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\n" ); document.write( " From the graph, we can see that the two lines intersect at the point (\"-4\",\"0\") (note: you might have to adjust the window to see the intersection)
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