document.write( "Question 457364: Write the equation of the line that satisfies the given conditions. Express the final equation in standard form.
\n" ); document.write( "Contains the point (-7, 2) and is perpendicular to the line 3x − y = 4
\n" ); document.write( "
\n" ); document.write( "

Algebra.Com's Answer #313806 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
\r
\n" ); document.write( "\n" ); document.write( "the point (-7, 2)\r
\n" ); document.write( "\n" ); document.write( "\"3x+%26%238722%3B+y+=+4+\".......->......\"3x+%26%238722%3B+4+=+y+\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: Finding the Equation of a Line Parallel or Perpendicular to a Given Line

\n" ); document.write( "
\n" ); document.write( " Remember, any two perpendicular lines are negative reciprocals of each other. So if you're given the slope of \"3\", you can find the perpendicular slope by this formula:
\n" ); document.write( "
\n" ); document.write( " \"m%5Bp%5D=-1%2Fm\" where \"m%5Bp%5D\" is the perpendicular slope
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"m%5Bp%5D=-1%2F%283%2F1%29\" So plug in the given slope to find the perpendicular slope
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"m%5Bp%5D=%28-1%2F1%29%281%2F3%29\" When you divide fractions, you multiply the first fraction (which is really \"1%2F1\") by the reciprocal of the second
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"m%5Bp%5D=-1%2F3\" Multiply the fractions.
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " So the perpendicular slope is \"-1%2F3\"
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " So now we know the slope of the unknown line is \"-1%2F3\" (its the negative reciprocal of \"3\" from the line \"y=3%2Ax-4\").\n" ); document.write( "Also since the unknown line goes through (-7,2), we can find the equation by plugging in this info into the point-slope formula
\n" ); document.write( "
\n" ); document.write( " Point-Slope Formula:
\n" ); document.write( "
\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
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"y-2=%28-1%2F3%29%2A%28x%2B7%29\" Plug in \"m=-1%2F3\", \"x%5B1%5D=-7\", and \"y%5B1%5D=2\"
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"y-2=%28-1%2F3%29%2Ax%2B%281%2F3%29%28-7%29\" Distribute \"-1%2F3\"
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"y-2=%28-1%2F3%29%2Ax-7%2F3\" Multiply
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"y=%28-1%2F3%29%2Ax-7%2F3%2B2\"Add \"2\" to both sides to isolate y
\n" ); document.write( "
\n" ); document.write( " \"y=%28-1%2F3%29%2Ax-7%2F3%2B6%2F3\" Make into equivalent fractions with equal denominators
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"y=%28-1%2F3%29%2Ax-1%2F3\" Combine the fractions
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"y=%28-1%2F3%29%2Ax-1%2F3\" Reduce any fractions
\n" ); document.write( "
\n" ); document.write( " So the equation of the line that is perpendicular to \"y=3%2Ax-4\" and goes through (\"-7\",\"2\") is \"y=%28-1%2F3%29%2Ax-1%2F3\"
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " So here are the graphs of the equations \"y=3%2Ax-4\" and \"y=%28-1%2F3%29%2Ax-1%2F3\"
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " graph of the given equation \"y=3%2Ax-4\" (red) and graph of the line \"y=%28-1%2F3%29%2Ax-1%2F3\"(green) that is perpendicular to the given graph and goes through (\"-7\",\"2\")
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" );