document.write( "Question 120451: for graphing.....2x-7y=8 and 3x-4y=-1 \n" ); document.write( "
Algebra.Com's Answer #88281 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( " \"2x-7y=8\"
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\n" ); document.write( " \"3x-4y=-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( " \"2x-7y=8\" Start with the given equation
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\n" ); document.write( " \"-7y=8-2x\" Subtract \"2+x\" from both sides
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\n" ); document.write( " \"-7y=-2x%2B8\" Rearrange the equation
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\n" ); document.write( " \"y=%28-2x%2B8%29%2F%28-7%29\" Divide both sides by \"-7\"
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\n" ); document.write( " \"y=%28-2%2F-7%29x%2B%288%29%2F%28-7%29\" Break up the fraction
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\n" ); document.write( " \"y=%282%2F7%29x-8%2F7\" Reduce
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\n" ); document.write( " Now lets graph \"y=%282%2F7%29x-8%2F7\" (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+%282%2F7%29x-8%2F7%29+\" Graph of \"y=%282%2F7%29x-8%2F7\"
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\n" ); document.write( " So let's solve for y on the second equation
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\n" ); document.write( " \"3x-4y=-1\" Start with the given equation
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\n" ); document.write( " \"-4y=-1-3x\" Subtract \"3+x\" from both sides
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\n" ); document.write( " \"-4y=-3x-1\" Rearrange the equation
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\n" ); document.write( " \"y=%28-3x-1%29%2F%28-4%29\" Divide both sides by \"-4\"
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\n" ); document.write( " \"y=%28-3%2F-4%29x%2B%28-1%29%2F%28-4%29\" Break up the fraction
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\n" ); document.write( " \"y=%283%2F4%29x%2B1%2F4\" Reduce
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\n" ); document.write( " Now lets add the graph of \"y=%283%2F4%29x%2B1%2F4\" to our first plot to get:
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\n" ); document.write( " Graph of \"y=%282%2F7%29x-8%2F7\"(red) and \"y=%283%2F4%29x%2B1%2F4\"(green)
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\n" ); document.write( " From the graph, we can see that the two lines intersect at the point (\"-3\",\"-2\") (note: you might have to adjust the window to see the intersection)
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