document.write( "Question 737500: I need to classify the system as consistent or inconsistent, and dependent or independent.
\n" ); document.write( "x + y = 8
\n" ); document.write( "x-y=4
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Algebra.Com's Answer #450398 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( " \"1x%2By=8\"
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\n" ); document.write( " \"1x-y=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( " \"1x%2By=8\" Start with the given equation
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\n" ); document.write( " \"1y=8-x\" Subtract \"+x\" from both sides
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\n" ); document.write( " \"1y=-x%2B8\" Rearrange the equation
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\n" ); document.write( " \"y=%28-x%2B8%29%2F%281%29\" Divide both sides by \"1\"
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\n" ); document.write( " \"y=%28-1%2F1%29x%2B%288%29%2F%281%29\" Break up the fraction
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\n" ); document.write( " \"y=-x%2B8\" Reduce
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\n" ); document.write( " Now lets graph \"y=-x%2B8\" (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+-x%2B8%29+\" Graph of \"y=-x%2B8\"
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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-y=4\" Start with the given equation
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\n" ); document.write( " \"-y=4-x\" Subtract \"+x\" from both sides
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\n" ); document.write( " \"-y=-x%2B4\" Rearrange the equation
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\n" ); document.write( " \"y=%28-x%2B4%29%2F%28-1%29\" Divide both sides by \"-1\"
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\n" ); document.write( " \"y=%28-1%2F-1%29x%2B%284%29%2F%28-1%29\" Break up the fraction
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\n" ); document.write( " \"y=x-4\" Reduce
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\n" ); document.write( " Now lets add the graph of \"y=x-4\" 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+-x%2B8%2Cx-4%29+\" Graph of \"y=-x%2B8\"(red) and \"y=x-4\"(green)
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\n" ); document.write( " From the graph, we can see that the two lines intersect at the point (\"6\",\"2\") (note: you might have to adjust the window to see the intersection)

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\n" ); document.write( "\n" ); document.write( "we usually use the word \"consistent\" when we are more interested in
\n" ); document.write( "indicating that the system does HAVE a solution, rather than
\n" ); document.write( "indicating how many solutions it has\r
\n" ); document.write( "\n" ); document.write( " \"Inconsistent\" means no solution,\r
\n" ); document.write( "\n" ); document.write( " \"Independent\" and \"Dependent\" BOTH mean there \"is\" a solution \r
\n" ); document.write( "\n" ); document.write( "since your system has solution (one intersection point), it is \"Independent\" or \"Dependent\"
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