document.write( "Question 1002806: 5x+y=21
\n" ); document.write( "4x+3y=8. Solution as an ordered pair?
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Algebra.Com's Answer #619669 by MathLover1(20850)\"\" \"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( " \"5x%2By=21\"
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\n" ); document.write( " \"4x%2B3y=8\"
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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( " \"5x%2By=21\" Start with the given equation
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\n" ); document.write( " \"1y=21-5x\" Subtract \"5+x\" from both sides
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\n" ); document.write( " \"1y=-5x%2B21\" Rearrange the equation
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\n" ); document.write( " \"y=%28-5x%2B21%29%2F%281%29\" Divide both sides by \"1\"
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\n" ); document.write( " \"y=%28-5%2F1%29x%2B%2821%29%2F%281%29\" Break up the fraction
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\n" ); document.write( " \"y=-5x%2B21\" Reduce
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\n" ); document.write( " Now lets graph \"y=-5x%2B21\" (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+-5x%2B21%29+\" Graph of \"y=-5x%2B21\"
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\n" ); document.write( " So let's solve for y on the second equation
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\n" ); document.write( " \"4x%2B3y=8\" Start with the given equation
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\n" ); document.write( " \"3y=8-4x\" Subtract \"4+x\" from both sides
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\n" ); document.write( " \"3y=-4x%2B8\" Rearrange the equation
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\n" ); document.write( " \"y=%28-4x%2B8%29%2F%283%29\" Divide both sides by \"3\"
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\n" ); document.write( " \"y=%28-4%2F3%29x%2B%288%29%2F%283%29\" Break up the fraction
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\n" ); document.write( " \"y=%28-4%2F3%29x%2B8%2F3\" Reduce
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\n" ); document.write( " Now lets add the graph of \"y=%28-4%2F3%29x%2B8%2F3\" 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+-5x%2B21%2C%28-4%2F3%29x%2B8%2F3%29+\" Graph of \"y=-5x%2B21\"(red) and \"y=%28-4%2F3%29x%2B8%2F3\"(green)
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\n" ); document.write( " From the graph, we can see that the two lines intersect at the point (\"5\",\"-4\") (note: you might have to adjust the window to see the intersection)
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