Results 1 to 9 of 9

Thread: In desperate need of Math Help!!!! +rep

  1. #1

    Join Date
    Dec 2011
    Posts
    5,821
    Userbars
    10
    Thanks
    1,505
    Thanked 2,151 Times in 1,219 Posts
    Downloads
    6
    Uploads
    0
    Mentioned
    1097 Post(s)
    Time Online
    43 d 10 h 26 m
    Avg. Time Online
    18 m
    Rep Power
    19

    In desperate need of Math Help!!!! +rep

    i have a few questions that are really pissing me off. if anyone could walk me through them i would greatly appreciate it.

    also i will +rep anyone who can help.




    Find the Vertex of the function (put the function in vertex for first): f(x)=8+2x-x^2
    [9/3/12 11:11:58 PM] Joanna: sigh
    [9/3/12 11:12:14 PM] Joanna: john
    [9/3/12 11:12:16 PM] Joanna: is
    [9/3/12 11:12:17 PM] Joanna: perfect

  2. #2
    Ray-Chill's Avatar
    Join Date
    Dec 2011
    Posts
    608
    Userbars
    3
    Thanks
    683
    Thanked 243 Times in 139 Posts
    Downloads
    100
    Uploads
    0
    Mentioned
    103 Post(s)
    Time Online
    5 d 3 h 33 m
    Avg. Time Online
    2 m
    Rep Power
    11
    =] Awesome! We just learned about this.
    xD
    Firstly, put your equation into the format ax^2+bx+c=0. I'm assuming you know the quadratic formula to find the x intercepts,
    x = (-b +or- SQRT(b^2-4ac))/2a

    The vertex will lie on the axis of symmetry of the parabola, which is halfway between the x-intercepts ie -b/2a. Use that to work out x, and then substitute it back into the quadratic to find the y value.

    Eg1. y=-x^2+2x+8 here a=-1, b=2 and c=8
    So -b/2a = -2/2(-1)
    = 1
    Then substitute x=1 into the quadratic
    y=-1+2+8
    =9
    Therefore the vertex is (1, 9)
    ~ <3 ~ <3 ~ <3 ~ <3 ~


    ďOf course it hurts, itís a spanking. How else would it work?Ē


  3. #3
    Victoria's Avatar
    Join Date
    Dec 2011
    Posts
    707
    Userbars
    3
    Thanks
    112
    Thanked 366 Times in 196 Posts
    Downloads
    22
    Uploads
    0
    Mentioned
    133 Post(s)
    Time Online
    19 d 21 h 45 m
    Avg. Time Online
    8 m
    Rep Power
    11
    [Only registered and activated users can see links. ]

    its (-1.-9) according to this



    Infamous Joe is you.

  4. #4
    MasterMind0wnz's Avatar
    Join Date
    Dec 2011
    Posts
    302
    Userbars
    2
    Thanks
    52
    Thanked 58 Times in 38 Posts
    Downloads
    1
    Uploads
    0
    Mentioned
    33 Post(s)
    Time Online
    2 h 7 m
    Avg. Time Online
    N/A
    Rep Power
    10
    I have something that will help you greatly if you don't already know it. PM Me.

  5. #5

    Join Date
    Dec 2011
    Posts
    5,821
    Userbars
    10
    Thanks
    1,505
    Thanked 2,151 Times in 1,219 Posts
    Downloads
    6
    Uploads
    0
    Mentioned
    1097 Post(s)
    Time Online
    43 d 10 h 26 m
    Avg. Time Online
    18 m
    Rep Power
    19
    ack is it negative or positive?
    [9/3/12 11:11:58 PM] Joanna: sigh
    [9/3/12 11:12:14 PM] Joanna: john
    [9/3/12 11:12:16 PM] Joanna: is
    [9/3/12 11:12:17 PM] Joanna: perfect

  6. #6
    zlolekim's Avatar
    Join Date
    Dec 2011
    Posts
    601
    Userbars
    5
    Thanks
    64
    Thanked 84 Times in 64 Posts
    Downloads
    52
    Uploads
    0
    Mentioned
    48 Post(s)
    Time Online
    2 d 22 h 39 m
    Avg. Time Online
    1 m
    Rep Power
    10
    Its positive John

  7. #7
    MasterMind0wnz's Avatar
    Join Date
    Dec 2011
    Posts
    302
    Userbars
    2
    Thanks
    52
    Thanked 58 Times in 38 Posts
    Downloads
    1
    Uploads
    0
    Mentioned
    33 Post(s)
    Time Online
    2 h 7 m
    Avg. Time Online
    N/A
    Rep Power
    10
    Vertex: (1,9)

  8. #8
    Victoria's Avatar
    Join Date
    Dec 2011
    Posts
    707
    Userbars
    3
    Thanks
    112
    Thanked 366 Times in 196 Posts
    Downloads
    22
    Uploads
    0
    Mentioned
    133 Post(s)
    Time Online
    19 d 21 h 45 m
    Avg. Time Online
    8 m
    Rep Power
    11
    sorry for giving you the wrong answer ^_^ i just googled it seemed legit!



    Infamous Joe is you.

  9. #9

    Join Date
    Dec 2011
    Posts
    5,821
    Userbars
    10
    Thanks
    1,505
    Thanked 2,151 Times in 1,219 Posts
    Downloads
    6
    Uploads
    0
    Mentioned
    1097 Post(s)
    Time Online
    43 d 10 h 26 m
    Avg. Time Online
    18 m
    Rep Power
    19
    thanks guys! repping everyone who helped
    [9/3/12 11:11:58 PM] Joanna: sigh
    [9/3/12 11:12:14 PM] Joanna: john
    [9/3/12 11:12:16 PM] Joanna: is
    [9/3/12 11:12:17 PM] Joanna: perfect

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •