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Homework Help: Quadratic Equation (Check my Workings ?)

  1. Dec 5, 2011 #1
    1. The problem statement, all variables and given/known data

    Solve using the formula method.

    2. Relevant equations

    [itex]3t^2+7t=5[/itex]

    3. The attempt at a solution

    [itex] 3t^2+7t-5=0
    t= \frac{-7 +or-\sqrt{7^2-4(3)(-5)}}{2(3)}

    t= \frac{-7+\sqrt{109}}{4}
    t= -4.39
    [/itex] OR...
    [itex]t= \frac{-7-\sqrt{109}}{4}
    t= -9.61 [/itex]

    The reason I have doubts is because the answer book from the tutor shows, T= 0.573 or -2.907... ? :(
     
  2. jcsd
  3. Dec 5, 2011 #2
    Ah ****, misuse of the formula tags, :( For some reason it wont let me go back and edit, hope you guys can understnad that :/
     
  4. Dec 5, 2011 #3

    eumyang

    User Avatar
    Homework Helper

    In the denominator, 2(3) does not equal 4.
     
  5. Dec 5, 2011 #4
    Oh! Such a silly mistake, I feel like a fool now !
     
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