Results 1 to 3 of 3

Math Help - AHHHH help! completing the square

  1. #1
    Newbie
    Joined
    Nov 2012
    From
    Ohio
    Posts
    8

    AHHHH help! completing the square

    So I have a problem that I cannot figure out for crap. Please walk through by COMPLETING THE SQUARE and getting what x equals.
    4n^2+12+5=0
    I know its (2n+1)(2n+5) but I need to know how to do it by completing the square so my first thing was 4n^2+12+36=31.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member
    Joined
    Jul 2012
    From
    INDIA
    Posts
    834
    Thanks
    209

    Re: AHHHH help! completing the square

    4n^2 + 12 n + 5 = 0
    it is always better to make coefficient of square term as 1. So divide the equation by 4, we get
    n^2 + 3n + 5/4 = 0
    n^2 + 3n = - 5/4
    Add square of half the coefficient of n ( in this case ( 3/2)^2= 9/4 ) on both sides
    n^2 + 3n + ( 3/2 )^2= 9/4 - 5/4
    [n + 3/2]^2 = 1 that gives n + 3/2 = 1 or -1 that gives n = -1/2 OR -5/2
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Nov 2012
    From
    Ohio
    Posts
    8

    Re: AHHHH help! completing the square

    Wow thanks haha
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Completing the square
    Posted in the Algebra Forum
    Replies: 2
    Last Post: August 6th 2010, 05:31 AM
  2. Completing the square!!
    Posted in the Algebra Forum
    Replies: 2
    Last Post: January 22nd 2010, 10:16 PM
  3. completing square
    Posted in the Algebra Forum
    Replies: 2
    Last Post: October 16th 2009, 03:11 AM
  4. completing the square
    Posted in the Algebra Forum
    Replies: 1
    Last Post: October 15th 2009, 12:07 PM
  5. Help completing the square.
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: October 2nd 2009, 09:00 AM

Search Tags


/mathhelpforum @mathhelpforum