Results 1 to 4 of 4

Thread: [SOLVED] equation of line

  1. #1
    Newbie
    Joined
    Feb 2009
    Posts
    9

    [SOLVED] equation of line

    Find an equation for the line with the given properties.

    Perpendicular to the line y=1/3x + 6; containing the point (2,-2)
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Member
    Joined
    Dec 2008
    Posts
    130
    Quote Originally Posted by Ashley189 View Post
    Find an equation for the line with the given properties.

    Perpendicular to the line y=1/3x + 6; containing the point (2,-2)
    would have slope:

    $\displaystyle m=-3$

    $\displaystyle (a, b)=(2, -2)$

    so

    $\displaystyle y+2=-3(x-2)$ from $\displaystyle y-b=m(x-a)$.

    $\displaystyle \Box$
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Feb 2009
    Posts
    9
    Quote Originally Posted by GaloisTheory1 View Post
    would have slope:

    $\displaystyle m=-3$

    $\displaystyle (a, b)=(2, -2)$

    so

    $\displaystyle y+2=-3(x-2)$ from $\displaystyle y-b=m(x-a)$.

    $\displaystyle \Box$
    I get it a little bit, but I'm still kinda confused.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor
    Joined
    Sep 2008
    From
    West Malaysia
    Posts
    1,261
    Thanks
    1
    Quote Originally Posted by Ashley189 View Post
    Find an equation for the line with the given properties.

    Perpendicular to the line y=1/3x + 6; containing the point (2,-2)

    You know the line is perpendicular to y=1/3x+6 so we can find its gradient .

    using the formula $\displaystyle m_1m_2=-1$ , we find that its gradient is -3.

    This line passes through point (2,-2)

    Using this formula , $\displaystyle y-y_1=m(x-x_1)$

    Substitute appropriately , we get $\displaystyle y-(-2)=-3(x-2)$ and simplify it ,
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. [SOLVED] Line equation ??
    Posted in the Algebra Forum
    Replies: 4
    Last Post: Aug 5th 2009, 08:14 PM
  2. [SOLVED] Finding the equation of a line in 3D
    Posted in the Calculus Forum
    Replies: 2
    Last Post: Apr 8th 2009, 02:35 PM
  3. [SOLVED] Equation of line
    Posted in the Algebra Forum
    Replies: 5
    Last Post: Feb 13th 2009, 03:47 PM
  4. [SOLVED] Help finding the equation of a line
    Posted in the Algebra Forum
    Replies: 2
    Last Post: Feb 13th 2009, 02:26 PM
  5. [SOLVED] Equation of a line 2
    Posted in the Algebra Forum
    Replies: 6
    Last Post: Feb 13th 2009, 01:53 PM

Search Tags


/mathhelpforum @mathhelpforum