document.write( "Question 1100209: y=2x-4 and x+2y=12
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Algebra.Com's Answer #714698 by richwmiller(17219)\"\" \"About 
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y=2x-4 and x+2y=12
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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-y=4\"
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\n" ); document.write( " \"1x%2B2y=12\"
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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-y=4\" Start with the given equation
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\n" ); document.write( " \"-y=4-2x\" Subtract \"2+x\" from both sides
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\n" ); document.write( " \"-y=-2x%2B4\" Rearrange the equation
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\n" ); document.write( " \"y=%28-2x%2B4%29%2F%28-1%29\" Divide both sides by \"-1\"
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\n" ); document.write( " \"y=%28-2%2F-1%29x%2B%284%29%2F%28-1%29\" Break up the fraction
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\n" ); document.write( " \"y=2x-4\" Reduce
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\n" ); document.write( " Now lets graph \"y=2x-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+2x-4%29+\" Graph of \"y=2x-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%2B2y=12\" Start with the given equation
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\n" ); document.write( " \"2y=12-x\" Subtract \"+x\" from both sides
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\n" ); document.write( " \"2y=-x%2B12\" Rearrange the equation
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\n" ); document.write( " \"y=%28-x%2B12%29%2F%282%29\" Divide both sides by \"2\"
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\n" ); document.write( " \"y=%28-1%2F2%29x%2B%2812%29%2F%282%29\" Break up the fraction
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\n" ); document.write( " \"y=%28-1%2F2%29x%2B6\" Reduce
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\n" ); document.write( " Now lets add the graph of \"y=%28-1%2F2%29x%2B6\" 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-4%2C%28-1%2F2%29x%2B6%29+\" Graph of \"y=2x-4\"(red) and \"y=%28-1%2F2%29x%2B6\"(green)
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\n" ); document.write( " From the graph, we can see that the two lines intersect at the point (\"4\",\"4\") (note: you might have to adjust the window to see the intersection)

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