Results 1 to 9 of 9

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

  1. #1

    Join Date
    Dec 2011
    Gender
    Location
    United States
    Posts
    5,856
    Thanks
    1,493
    Thanked 2,146 Times in 1,216 Posts


    Downloads
    6
    Uploads
    0
    Mentioned
    1092 Post(s)
    Time Online
    42 d 18 h 30 m
    Avg. Time Online
    32 m
    Rep Power
    16

    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

  2. #2
    Queen of Candy Land Ray-Chill's Avatar
    Join Date
    Dec 2011
    Gender
    Location
    Tacoma
    Posts
    619
    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
    3 m
    Rep Power
    7
    =] 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
    Victoria's Avatar
    Join Date
    Dec 2011
    Gender
    Location
    In a pineapple under the sea.
    Posts
    710
    Thanks
    114
    Thanked 367 Times in 198 Posts


    Downloads
    22
    Uploads
    0
    Mentioned
    133 Post(s)
    Time Online
    19 d 19 h 14 m
    Avg. Time Online
    15 m
    Rep Power
    7

  4. #4
    MasterMind0wnz's Avatar
    Join Date
    Dec 2011
    Location
    Long Beach, California
    Posts
    304
    Thanks
    52
    Thanked 59 Times in 39 Posts


    Downloads
    1
    Uploads
    0
    Mentioned
    33 Post(s)
    Time Online
    2 h 7 m
    Avg. Time Online
    N/A
    Rep Power
    7
    I have something that will help you greatly if you don't already know it. PM Me.

  5. #5

    Join Date
    Dec 2011
    Gender
    Location
    United States
    Posts
    5,856
    Thanks
    1,493
    Thanked 2,146 Times in 1,216 Posts


    Downloads
    6
    Uploads
    0
    Mentioned
    1092 Post(s)
    Time Online
    42 d 18 h 30 m
    Avg. Time Online
    32 m
    Rep Power
    16
    ack is it negative or positive?

  6. #6
    zlolekim's Avatar
    Join Date
    Dec 2011
    Gender
    Location
    NYC
    Posts
    608
    Thanks
    62
    Thanked 80 Times in 60 Posts


    Downloads
    41
    Uploads
    0
    Mentioned
    48 Post(s)
    Time Online
    2 d 2 h 35 m
    Avg. Time Online
    1 m
    Rep Power
    7
    Its positive John

  7. #7
    MasterMind0wnz's Avatar
    Join Date
    Dec 2011
    Location
    Long Beach, California
    Posts
    304
    Thanks
    52
    Thanked 59 Times in 39 Posts


    Downloads
    1
    Uploads
    0
    Mentioned
    33 Post(s)
    Time Online
    2 h 7 m
    Avg. Time Online
    N/A
    Rep Power
    7
    Vertex: (1,9)

  8. #8
    Victoria's Avatar
    Join Date
    Dec 2011
    Gender
    Location
    In a pineapple under the sea.
    Posts
    710
    Thanks
    114
    Thanked 367 Times in 198 Posts


    Downloads
    22
    Uploads
    0
    Mentioned
    133 Post(s)
    Time Online
    19 d 19 h 14 m
    Avg. Time Online
    15 m
    Rep Power
    7
    sorry for giving you the wrong answer ^_^ i just googled it seemed legit!

  9. #9

    Join Date
    Dec 2011
    Gender
    Location
    United States
    Posts
    5,856
    Thanks
    1,493
    Thanked 2,146 Times in 1,216 Posts


    Downloads
    6
    Uploads
    0
    Mentioned
    1092 Post(s)
    Time Online
    42 d 18 h 30 m
    Avg. Time Online
    32 m
    Rep Power
    16
    thanks guys! repping everyone who helped

Posting Permissions

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