document.write( "Question 655006: What is the point that is common to the graphs of both functions? y=1/2x+3 and y=-x-3
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Algebra.Com's Answer #408894 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "\"y=%281%2F2%29x%2B3\" and \"y=-x-3\" \r
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\n" ); document.write( "\n" ); document.write( "\"%281%2F2%29x-y=-3\" and \"-x-y=3\" \r
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Solved by pluggable solver: Solve the System of Equations by Graphing

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\n" ); document.write( " Let's look at the first equation \"%281%2F2%29x-y=-3\"
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\n" ); document.write( " \"2%28%281%2F2%29x-y%29=2%28-3%29\" Multiply both sides of the first equation by the LCD 2
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\n" ); document.write( " \"1x-2y=-6\" Distribute
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\n" ); document.write( " So our new system of equations is:
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\n" ); document.write( " \"1x-2y=-6\"
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\n" ); document.write( " \"-x-y=3\"
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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-2y=-6\" Start with the given equation
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\n" ); document.write( " \"-2y=-6-x\" Subtract \"+x\" from both sides
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\n" ); document.write( " \"-2y=-x-6\" Rearrange the equation
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\n" ); document.write( " \"y=%28-x-6%29%2F%28-2%29\" Divide both sides by \"-2\"
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\n" ); document.write( " \"y=%28-1%2F-2%29x%2B%28-6%29%2F%28-2%29\" Break up the fraction
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\n" ); document.write( " \"y=%281%2F2%29x%2B3\" Reduce
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\n" ); document.write( " Now lets graph \"y=%281%2F2%29x%2B3\" (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+%281%2F2%29x%2B3%29+\" Graph of \"y=%281%2F2%29x%2B3\"
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\n" ); document.write( " So let's solve for y on the second equation
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\n" ); document.write( " \"-x-y=3\" Start with the given equation
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\n" ); document.write( " \"-y=3%2Bx\" Add \"+x\" to both sides
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\n" ); document.write( " \"-y=%2Bx%2B3\" Rearrange the equation
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\n" ); document.write( " \"y=%28%2Bx%2B3%29%2F%28-1%29\" Divide both sides by \"-1\"
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\n" ); document.write( " \"y=%28%2B1%2F-1%29x%2B%283%29%2F%28-1%29\" Break up the fraction
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\n" ); document.write( " \"y=-x-3\" Reduce
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\n" ); document.write( " Now lets add the graph of \"y=-x-3\" 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+%281%2F2%29x%2B3%2C-x-3%29+\" Graph of \"y=%281%2F2%29x%2B3\"(red) and \"y=-x-3\"(green)
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\n" ); document.write( " From the graph, we can see that the two lines intersect at the point (\"-4\",\"1\") (note: you might have to adjust the window to see the intersection)
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