document.write( "Question 122319: I need to write the equation of the line that is perpendicular to the given line and passes through the given point. I am stuck and confused.\r
\n" ); document.write( "\n" ); document.write( "Here is the equation
\n" ); document.write( "y=-2x-1 (2,6)\r
\n" ); document.write( "\n" ); document.write( "Here is what I have
\n" ); document.write( "y=mx+b
\n" ); document.write( "6=-2(2)+b
\n" ); document.write( "6=-4+b
\n" ); document.write( "6+4=-4+b+4
\n" ); document.write( "10=b\r
\n" ); document.write( "\n" ); document.write( "y=1/2x+10
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Algebra.Com's Answer #89809 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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Solved by pluggable solver: Finding the Equation of a Line Parallel or Perpendicular to a Given Line

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\n" ); document.write( " Remember, any two perpendicular lines are negative reciprocals of each other. So if you're given the slope of \"-2\", you can find the perpendicular slope by this formula:
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\n" ); document.write( " \"m%5Bp%5D=-1%2Fm\" where \"m%5Bp%5D\" is the perpendicular slope
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\n" ); document.write( " \"m%5Bp%5D=-1%2F%28-2%2F1%29\" So plug in the given slope to find the perpendicular slope
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\n" ); document.write( " \"m%5Bp%5D=%28-1%2F1%29%281%2F-2%29\" When you divide fractions, you multiply the first fraction (which is really \"1%2F1\") by the reciprocal of the second
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\n" ); document.write( " \"m%5Bp%5D=1%2F2\" Multiply the fractions.
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\n" ); document.write( " So the perpendicular slope is \"1%2F2\"
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\n" ); document.write( " So now we know the slope of the unknown line is \"1%2F2\" (its the negative reciprocal of \"-2\" from the line \"y=-2%2Ax-1\").\n" ); document.write( "Also since the unknown line goes through (2,6), we can find the equation by plugging in this info into the point-slope formula
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\n" ); document.write( " Point-Slope Formula:
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\n" ); document.write( " \"y-y%5B1%5D=m%28x-x%5B1%5D%29\" where m is the slope and (\"x%5B1%5D\",\"y%5B1%5D\") is the given point
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\n" ); document.write( " \"y-6=%281%2F2%29%2A%28x-2%29\" Plug in \"m=1%2F2\", \"x%5B1%5D=2\", and \"y%5B1%5D=6\"
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\n" ); document.write( " \"y-6=%281%2F2%29%2Ax-%281%2F2%29%282%29\" Distribute \"1%2F2\"
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\n" ); document.write( " \"y-6=%281%2F2%29%2Ax-2%2F2\" Multiply
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\n" ); document.write( " \"y=%281%2F2%29%2Ax-2%2F2%2B6\"Add \"6\" to both sides to isolate y
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\n" ); document.write( " \"y=%281%2F2%29%2Ax-2%2F2%2B12%2F2\" Make into equivalent fractions with equal denominators
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\n" ); document.write( " \"y=%281%2F2%29%2Ax%2B10%2F2\" Combine the fractions
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\n" ); document.write( " \"y=%281%2F2%29%2Ax%2B5\" Reduce any fractions
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\n" ); document.write( " So the equation of the line that is perpendicular to \"y=-2%2Ax-1\" and goes through (\"2\",\"6\") is \"y=%281%2F2%29%2Ax%2B5\"
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\n" ); document.write( " So here are the graphs of the equations \"y=-2%2Ax-1\" and \"y=%281%2F2%29%2Ax%2B5\"
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\n" ); document.write( " graph of the given equation \"y=-2%2Ax-1\" (red) and graph of the line \"y=%281%2F2%29%2Ax%2B5\"(green) that is perpendicular to the given graph and goes through (\"2\",\"6\")
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