Results 1 to 5 of 5

Math Help - Quadratic equation from given roots.

  1. #1
    Newbie
    Joined
    Mar 2007
    Posts
    6

    Question Quadratic equation from given roots.

    Quadratic equation from given roots.
    For example if the roots were -6 and 2 how would I write quadratic equation.
    Last edited by power2600; March 14th 2007 at 10:33 PM.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Grand Panjandrum
    Joined
    Nov 2005
    From
    someplace
    Posts
    14,972
    Thanks
    4
    Quote Originally Posted by power2600 View Post
    Quadratic equation from given roots.
    For example if the roots were -6 and 2 how would I write quadratic equation.
    (x-(-6))(x-2) = (x+6)(x-2) = x^2 + 4x -12 = 0

    RonL
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Mar 2007
    Posts
    6
    Thanks for the help

    Also, while I am on the subject of quadratic equations
    I have been having some trouble with Solving 2 var quadratic equations.
    Example: h=-16t^2+80t+2
    Solve for both t and h.

    I get:
    t= +-(sqrt {102-h+10})/4
    Follow Math Help Forum on Facebook and Google+

  4. #4
    is up to his old tricks again! Jhevon's Avatar
    Joined
    Feb 2007
    From
    New York, USA
    Posts
    11,663
    Thanks
    3
    Quote Originally Posted by power2600 View Post
    Thanks for the help

    Also, while I am on the subject of quadratic equations
    I have been having some trouble with Solving 2 var quadratic equations.
    Example: h=-16t^2+80t+2
    Solve for both t and h.

    I get:
    t= +-(sqrt {102-h+10})/4
    i didn't check if you solved for t correctly, but i'll tell you this. you can't solve for 2 unknowns with one equation. you need two equations to solve 2 unknowns, and 3 to solve for 3 and so on. you can solve for one unknown in terms of the other, as you did (you solved for t in terms of h), but that's about it. unless you were given some other condition
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Global Moderator

    Joined
    Nov 2005
    From
    New York City
    Posts
    10,616
    Thanks
    10
    Quote Originally Posted by Jhevon View Post
    i didn't check if you solved for t correctly, but i'll tell you this. you can't solve for 2 unknowns with one equation. you need two equations to solve 2 unknowns, and 3 to solve for 3 and so on. you can solve for one unknown in terms of the other, as you did (you solved for t in terms of h), but that's about it. unless you were given some other condition
    Not always true.

    Say x,y,z>= 0

    Solve for:

    x^3+y^3+z^3 = xyz



    Example 2:

    Solve for:

    x^3=y^2+1

    Where x,y are positive integrers.

    It turns out you CAN solve them.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. roots of the quadratic equation
    Posted in the Algebra Forum
    Replies: 3
    Last Post: July 27th 2010, 04:32 AM
  2. Roots of quadratic equation
    Posted in the Pre-Calculus Forum
    Replies: 4
    Last Post: June 23rd 2010, 05:08 AM
  3. roots of quadratic equation
    Posted in the Algebra Forum
    Replies: 3
    Last Post: May 31st 2009, 03:49 AM
  4. The roots of a quadratic equation
    Posted in the Math Topics Forum
    Replies: 2
    Last Post: December 1st 2008, 07:50 AM
  5. Roots of quadratic equation
    Posted in the Algebra Forum
    Replies: 2
    Last Post: October 13th 2008, 12:05 AM

Search Tags


/mathhelpforum @mathhelpforum