Results 1 to 2 of 2

Math Help - 4 questions i can not figure out **HELP PLEASE**

  1. #1
    Newbie
    Joined
    Mar 2008
    Posts
    3

    4 questions i can not figure out **HELP PLEASE**

    I had 4 questions, i wrote em up in photoshop i thought it would be easier.

    1.


    2.


    3.


    4.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Member Danshader's Avatar
    Joined
    Mar 2008
    From
    http://en.wikipedia.org/wiki/Malaysia now stop asking me where is malaysia...
    Posts
    158
    1) using the line euqation
    y = mx +c

    where y = price
    x = number of cds

    substituting y = 490 and x = 80

    490 = 80m + c -------(1)

    similarly

    640 = 200m + c -------(2)

    solving the simultaneous equation:

    m = 1.25
    c = 390

    final equation:

    y = 1.25x + 390


    3) the closest point on the line to the origin creates a line perpendicular which joins the origin and the point on the line closest to the origin to that particular line concerned.

    given the equation of the line is 2x + y -2 = 0 → y = -2x + 2---------(1)
    using
    m1(m2) = -1
    the gradient of the other line is 1/2

    from y = mx +c
    substituting the gradient of the new line
    y = 1/2x +c

    also since it passes through the origin (0,0)

    0 = (1/2)(0) + c
    c = 0

    equation of new line:

    y = x/2 ---------(2)

    solving the simultaneous equation (1) and (2)

    y = 2/5
    x = 4/5
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. [SOLVED] Finding the Angle in this Figure (see the figure)
    Posted in the Geometry Forum
    Replies: 1
    Last Post: December 19th 2011, 02:44 PM
  2. Replies: 3
    Last Post: October 21st 2010, 08:46 AM
  3. Replies: 2
    Last Post: June 4th 2010, 07:02 AM
  4. two easy questions I can't figure out
    Posted in the Advanced Statistics Forum
    Replies: 1
    Last Post: December 10th 2009, 03:42 PM
  5. Replies: 2
    Last Post: March 6th 2009, 07:49 AM

Search Tags


/mathhelpforum @mathhelpforum