Results 1 to 6 of 6

Math Help - slope of 1/3

  1. #1
    Junior Member
    Joined
    Aug 2012
    From
    Winnipeg
    Posts
    57

    slope of 1/3

    Can a line drawn through (-4,-3) have a slope of 1/3???
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    skeeter's Avatar
    Joined
    Jun 2008
    From
    North Texas
    Posts
    12,110
    Thanks
    982

    Re: slope of 1/3

    any slope you want thru any point in the plane ...
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Member
    Joined
    Sep 2012
    From
    Planet Earth
    Posts
    215
    Thanks
    56

    Re: slope of 1/3

    Of course it can. A line drawn through any particular point can have any slope, because those two pieces of information aren't conflicting.

    Think about it: if the line passes through (-4,-3), that is its starting point, a piece of information. The slope then tells you in what manner the line "leaves" the point - if the slope is 0, it will be purely horizontal, if the slope is a large number, it will be almost vertical. But no matter what the slope is, the line will always exist, just by spinning it about (-4,-3).

    To find the equation of this line, remember that a graph with slope 1/3 will have the following form:

    y = (1/3)*x + c

    Now solve for c by plugging in the point:

    -3 = (1/3)*(-4) + c
    c = -3 - (1/3)*(-4) = -5/3

    So

    y = (x - 5)/3

    Double-check that this is correct by plugging in x = -4:

    -4 - 5 = -9, then dividing by 3 equals -3, as required.
    Last edited by SworD; September 6th 2012 at 06:03 PM.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Junior Member
    Joined
    Aug 2012
    From
    Winnipeg
    Posts
    57

    Re: slope of 1/3

    How can I state the coordinates of two other points on this line?
    Follow Math Help Forum on Facebook and Google+

  5. #5
    MHF Contributor
    skeeter's Avatar
    Joined
    Jun 2008
    From
    North Texas
    Posts
    12,110
    Thanks
    982

    Re: slope of 1/3

    from (-4,-3) , delta x = 3 , delta y = 1 ... (-1, -2)

    do it again from the new point (-1,-2)
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Junior Member
    Joined
    Aug 2012
    From
    Winnipeg
    Posts
    57

    Re: slope of 1/3

    I got it already. Thank you. I did a wrong drawing like (-4,0) and (0.-3) and not just (-4.-3). That is why I was so confused, because of the given slope of 1/3. And then it was not possible to draw it with a slope of 1/3.
    No everything is clear.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 6
    Last Post: September 11th 2011, 05:53 PM
  2. Replies: 2
    Last Post: September 16th 2009, 09:13 PM
  3. Secant Line Slope and Tangent Line Slope
    Posted in the Calculus Forum
    Replies: 3
    Last Post: August 26th 2009, 06:40 PM
  4. Slope...
    Posted in the Algebra Forum
    Replies: 2
    Last Post: April 19th 2007, 04:49 AM
  5. slope
    Posted in the Calculus Forum
    Replies: 22
    Last Post: April 11th 2007, 10:59 AM

Search Tags


/mathhelpforum @mathhelpforum