document.write( "Question 687311: I have a test tomorrow, I have no clue how to graph this:
\n" ); document.write( "Solve the system graphically:
\n" ); document.write( " -3x + y = 7
\n" ); document.write( "-4x +4y +12
\n" ); document.write( "I got this so far :
\n" ); document.write( "y + 3x + 7
\n" ); document.write( " y = x + 3
\n" ); document.write( "Then they want me to graph it. Everyone tries to tell help me, but only makes it more confusing.
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Algebra.Com's Answer #425111 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( " \"-3x%2By=7\"
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\n" ); document.write( " \"-4x%2B4y=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( " \"-3x%2By=7\" Start with the given equation
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\n" ); document.write( " \"1y=7%2B3x\" Add \"3+x\" to both sides
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\n" ); document.write( " \"1y=%2B3x%2B7\" Rearrange the equation
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\n" ); document.write( " \"y=%28%2B3x%2B7%29%2F%281%29\" Divide both sides by \"1\"
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\n" ); document.write( " \"y=%28%2B3%2F1%29x%2B%287%29%2F%281%29\" Break up the fraction
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\n" ); document.write( " \"y=3x%2B7\" Reduce
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\n" ); document.write( " Now lets graph \"y=3x%2B7\" (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+3x%2B7%29+\" Graph of \"y=3x%2B7\"
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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%2B4y=12\" Start with the given equation
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\n" ); document.write( " \"4y=12%2B4x\" Add \"4+x\" to both sides
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\n" ); document.write( " \"4y=%2B4x%2B12\" Rearrange the equation
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\n" ); document.write( " \"y=%28%2B4x%2B12%29%2F%284%29\" Divide both sides by \"4\"
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\n" ); document.write( " \"y=%28%2B4%2F4%29x%2B%2812%29%2F%284%29\" Break up the fraction
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\n" ); document.write( " \"y=x%2B3\" Reduce
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\n" ); document.write( " Now lets add the graph of \"y=x%2B3\" 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+3x%2B7%2Cx%2B3%29+\" Graph of \"y=3x%2B7\"(red) and \"y=x%2B3\"(green)
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\n" ); document.write( " From the graph, we can see that the two lines intersect at the point (\"-2\",\"1\") (note: you might have to adjust the window to see the intersection)
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