document.write( "Question 111979: Find values for m and b in the following system so that the solution to the system is (-3,4)
\n" ); document.write( "5x+7y=b
\n" ); document.write( "mx+y=22
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Algebra.Com's Answer #81689 by MathLover1(20849)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "Find values for m and b in the following system so that the solution to the system is (-3,4)\r
\n" ); document.write( "\n" ); document.write( "\"5x%2B7y=b\"\r
\n" ); document.write( "\n" ); document.write( "\"mx%2By=22\"\r
\n" ); document.write( "\n" ); document.write( "Since (x,y) = (-3,4), we will have:\r
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\n" ); document.write( "\n" ); document.write( "\"5%2A%28-3%29+%2B+7%2A4+=+b\" \r
\n" ); document.write( "\n" ); document.write( "\"m%2A%28-3%29+%2B+4+=+22\"
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\n" ); document.write( "\"-+15+%2B+28+=+b\"…………..=> \"b+=+13\"\r
\n" ); document.write( "\n" ); document.write( "\"-3m+%2B+4+=+22\"…………..=> \"-3m+=+22+%96+4\"…….=>\"-3m+=+18\"….=> \"m+=+18%2F%28-3%29\"…..=> \"m+=+-6\"\r
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\n" ); document.write( "\n" ); document.write( "From the graph we can see that the intersection is (\"-3\", \"4\"). \r
\n" ); document.write( "\n" ); document.write( "This means \"the\"\"+solution\" is (\"-3\", \"4\") which means \"x=-3\" and \"y=4\".\r
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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%2B7y=13\"
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\n" ); document.write( " \"-6x%2By=22\"
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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%2B7y=13\" Start with the given equation
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\n" ); document.write( " \"7y=13-5x\" Subtract \"5+x\" from both sides
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\n" ); document.write( " \"7y=-5x%2B13\" Rearrange the equation
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\n" ); document.write( " \"y=%28-5x%2B13%29%2F%287%29\" Divide both sides by \"7\"
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\n" ); document.write( " \"y=%28-5%2F7%29x%2B%2813%29%2F%287%29\" Break up the fraction
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\n" ); document.write( " \"y=%28-5%2F7%29x%2B13%2F7\" Reduce
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\n" ); document.write( " Now lets graph \"y=%28-5%2F7%29x%2B13%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+%28-5%2F7%29x%2B13%2F7%29+\" Graph of \"y=%28-5%2F7%29x%2B13%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( " \"-6x%2By=22\" Start with the given equation
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\n" ); document.write( " \"1y=22%2B6x\" Add \"6+x\" to both sides
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\n" ); document.write( " \"1y=%2B6x%2B22\" Rearrange the equation
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\n" ); document.write( " \"y=%28%2B6x%2B22%29%2F%281%29\" Divide both sides by \"1\"
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\n" ); document.write( " \"y=%28%2B6%2F1%29x%2B%2822%29%2F%281%29\" Break up the fraction
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\n" ); document.write( " \"y=6x%2B22\" Reduce
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\n" ); document.write( " Now lets add the graph of \"y=6x%2B22\" 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+%28-5%2F7%29x%2B13%2F7%2C6x%2B22%29+\" Graph of \"y=%28-5%2F7%29x%2B13%2F7\"(red) and \"y=6x%2B22\"(green)
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\n" ); document.write( " From the graph, we can see that the two lines intersect at the point (\"-3\",\"4\") (note: you might have to adjust the window to see the intersection)

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