Maths Problem, Help Appriciated

Discussion in 'General Chat' started by bacanze, Jun 3, 2007.

  1. #1
    Hi

    Right I have a simple math problem, but I just cannot figure out how to work the answer out.

    3x[squared] - 2x = 96

    Basically, you need to find the value for x, which I think is 6, however once it gets to 108, im stuck on the -2x part as it wouldnt equal 96.

    Help appreciated:)
     
    bacanze, Jun 3, 2007 IP
  2. 8everything

    8everything Peon

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    #2
    I had a formula for this!!! consisted of a, b and c.. lol

    Anyways:
    3x^2 - 2x - 96 = 0

    Can't you just factorize it now? Which would give you (3x )( ) :p brain is too dead to solve it lol (you need a sum and product that equals to -96.. but don't neglect the 3x)
     
    8everything, Jun 3, 2007 IP
  3. 8^)

    8^) Peon

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    #3
    :confused: I hope you are nder 10
     
    8^), Jun 3, 2007 IP
  4. Computerized

    Computerized Well-Known Member

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    #4
    Yeah, like 8 said, just factor it out. In the end, it equals (3x+16)(x-6).

    I don't think you're supposed to solve for x, but 6 is correct if you do have to. Just substitute that in the formula to check: 3(6)^2 - 2(6) = 96
     
    Computerized, Jun 3, 2007 IP
  5. Katy

    Katy Moderator Staff

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    #5
    That's PQ, my friend! :p

    3x² - 2x - 96 = 0 | /3
    x² - 2/3x - 32 = 0

    2/6 +- root(4+1152)
    2/6 +- 34

    Ans1 = -101/3

    Ans2 = 103/3
     
    Katy, Jun 3, 2007 IP
  6. YIAM

    YIAM Notable Member

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    #6
    3x^2 - 2x = 96

    3x^2 - 2x - 96 = 0

    3x^2 -18x + 16x - 96 =0

    3x(x - 6) + 16(x - 6) = 0

    (3x+16)(x-6)=0

    So, x=6, -16/3


    :) :) I am the best :) :)
     
    YIAM, Jun 3, 2007 IP
  7. virusrulez

    virusrulez Peon

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    #7
    3x^2-2x=96
    3x^2-2x-96=0
    3x^2-18x+16x-96=0
    3x(x-6)+16(x-6)=0
    (x-6)(3x+16)=0
    hence x = 6 & x= -16/3
    simple :D
     
    virusrulez, Jun 3, 2007 IP
  8. RovingCalypso

    RovingCalypso Well-Known Member

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    #8
    Here is that formula (quadratic formula)

    You have the equation of the type
    a x^2 + b x + c =0

    The formula

    x = {- b + square root (b ^ 2 - 4(a)(c)) } / 2 (a) (First solution)

    x = {- b - square root (b ^ 2 - 4(a)(c)) } / 2 (a) (second solution)
     
    RovingCalypso, Jun 3, 2007 IP
  9. 8everything

    8everything Peon

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    #9
    :p exactly!!!! Right, now it's coming back to me.. l'equation quadratique. I learnt calc in french, my bad. Oops:eek:

    ( Very useful for solving those factorizing problems that don't have whole numbers in the response... )
     
    8everything, Jun 3, 2007 IP
  10. browie

    browie Peon

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    #10
    This guy got it first..... I'm a math teacher.
     
    browie, Jun 3, 2007 IP