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Homework Help: Calculus Question: Equations of Lines in 2-Space

  1. Mar 27, 2012 #1
    1. The problem statement, all variables and given/known data

    A line passes through the point (1, -4) and is perpendicular to the line 3x + 2y – 6 = 0. Determine a scalar equation for the line.

    Was also given this: Find a vector which is normal to the line and then use the dot product of this vector and P0P.

    2. Relevant equations

    scalar equation: ax+by+c=0

    3. The attempt at a solution

    i'm not sure if this gets me anywhere but i turned the scalar equation into a vector equation:
    Random point on line: (0,-3), therefore vector equation r=(0,-3)+t(2,-3)
    Not sure where i can go from here, i just know i have to find a line perpendicular to 3x + 2y - 6 =0 that goes through the point (1, -4)
    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
    Last edited: Mar 27, 2012
  2. jcsd
  3. Mar 27, 2012 #2


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    Gold Member

    Remember that a the coefficients of 3x+2y=6 give you a normal vector to the line. So use <3,2> for your direction vector and (1,-4) for your point. Write the vector equation using those and eliminate the parameter to get your scalar equation.
  4. Mar 27, 2012 #3
    Okay thank you very much
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