Results 1 to 3 of 3

Math Help - Have a quadratic function pass throught a given point

  1. #1
    Newbie
    Joined
    Aug 2008
    From
    Brisbane, Australia
    Posts
    15

    Have a quadratic function pass throught a given point

    Hi, I'm trying to create and plot a quadratic function that passes through the point (x,y) (50.8, 120).

    If I'm using the general form how would I tweak (presumably) the value of a in order to this?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Joined
    Apr 2005
    Posts
    1,631
    A quadratic function?
    Like in the form y = ax^2 +bx +c ?

    That will pass the point (50.8,120)

    Tweak the "a" so that the graph will pass through (50.8,120)?

    Okay, nothing will stop you from using the quadratic y = ax^2.
    You can forget about the bx and c....since they are not specifically called for.

    So,
    y = ax^2
    120 = a(50.8)^2
    a = 120 /(50.8)^2
    a = 0.0465

    That is it.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Aug 2008
    From
    Brisbane, Australia
    Posts
    15
    Yeah, thats pretty much what I ended up doing. Whilst I can graphically tweak the function to do that, it is of course not 100% precise.

    Thank very much all the same, I didn't think that there was a way to do that anyways (at least not easily).
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 1
    Last Post: August 25th 2011, 11:08 AM
  2. Replies: 6
    Last Post: February 12th 2011, 12:37 PM
  3. Replies: 5
    Last Post: August 8th 2009, 07:04 PM
  4. Replies: 1
    Last Post: November 6th 2008, 02:35 PM
  5. Circles point pass through
    Posted in the Geometry Forum
    Replies: 2
    Last Post: January 4th 2006, 05:05 AM

Search Tags


/mathhelpforum @mathhelpforum