Sender: Jimmy Lumpkins
Subject: Pre calculus

Need a method for solving the following problem: Find the equation of a line through point P that is parallel or perpendicular to another line.

Hi Jimmy,

  1. Find the slope of the given line (rearrange into y=mx+b form and then the slope is m)
  2. If the new line is to be parallel to the given line set its slope to m. If it is to be perpendicularto the given line set its slope to -1/m
  3. Use the formula y-y1=m(x-x1) where x1 and y1 are the co-ordinates of P m was calculated in 2 and x,y are the variables of the line.


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