Results 1 to 7 of 7

Math Help - x-intercept

  1. #1
    Newbie
    Joined
    Aug 2009
    Posts
    20

    x-intercept

    I cannot remember how to work this problem but here is what I think I am suppose to do.
    The problem states "Solve and give the solutions x=

    5x+x(x-2)=0
    do I mulitply
    5x+x^2 -2x = 0
    3x + x^2 = 0
    3x - 3x + x^2 = 0 - 3x
    This is the point were I feel I am on the wrong track can you help?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Junior Member
    Joined
    Aug 2009
    Posts
    66
    Quote Originally Posted by Brama Bull View Post
    I cannot remember how to work this problem but here is what I think I am suppose to do.
    The problem states "Solve and give the solutions x=

    5x+x(x-2)=0
    do I mulitply
    5x+x^2 -2x = 0
    3x + x^2 = 0
    3x - 3x + x^2 = 0 - 3x
    This is the point were I feel I am on the wrong track can you help?
    At the point where you have  3x + x^2 = 0 you have it in a form that is easily factorable, therefore easily solvable.

    Factor out the common x term from the left side:

     x(3 + x) = 0

    Then solve for x.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Aug 2009
    Posts
    20

    x-intercept

    the problem states find the x- intercept
    f(x)=5x+x(x-2).
    this is what I have done
    5x+x^2-2x
    x^2+3x
    x(x+3)
    now were do I go from here to find the x-intercept?
    Last edited by mr fantastic; August 21st 2009 at 03:25 AM. Reason: No edit - flagging the question as having been moved form another thread.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Junior Member
    Joined
    Aug 2009
    Posts
    66
    Quote Originally Posted by Brama Bull View Post
    the problem states find the x- intercept
    f(x)=5x+x(x-2).
    this is what I have done
    5x+x^2-2x
    x^2+3x
    x(x+3)
    now were do I go from here to find the x-intercept?
    Are you certain the problem does not ask for the y intercept? In the equation you wrote, which is quadratic, you have two real roots. They're normally not referred to as "x intercepts" in this context.
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Super Member 11rdc11's Avatar
    Joined
    Jul 2007
    From
    New Orleans
    Posts
    894
    Set x(x+3)=0, so your x int are 0. - 3
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Newbie
    Joined
    Aug 2009
    Posts
    20
    Yes it asks for the x- intercept; it can be in theses forms;(type an ordered pair, or simply your answer, type an exact answer using radicals as needed, express complex numbers in terms if i, Use a comma to seperate answers as needed)

    but I have double checked and it says the x-intercepts? I already have the solutions as (0,-3)
    Follow Math Help Forum on Facebook and Google+

  7. #7
    Super Member 11rdc11's Avatar
    Joined
    Jul 2007
    From
    New Orleans
    Posts
    894
    It may be reading (0,-3) as an ordered pair. Try this (0,0) and (-3,0)
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. intercept
    Posted in the Calculus Forum
    Replies: 7
    Last Post: June 11th 2011, 03:43 PM
  2. cut the y intercept
    Posted in the Algebra Forum
    Replies: 5
    Last Post: December 10th 2009, 03:14 PM
  3. intercept
    Posted in the Calculus Forum
    Replies: 1
    Last Post: July 14th 2009, 03:24 PM
  4. intercept help
    Posted in the Math Topics Forum
    Replies: 2
    Last Post: February 14th 2009, 06:32 AM
  5. x & y intercept
    Posted in the Pre-Calculus Forum
    Replies: 1
    Last Post: March 23rd 2007, 04:06 PM

Search Tags


/mathhelpforum @mathhelpforum