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Homework Help: Home Work Check / Algebra

  1. May 23, 2009 #1
    1. The problem statement, all variables and given/known data
    5/8x + 1/16x= 9/16 + x

    2. Relevant equations

    3. The attempt at a solution
    10x+ x = 9+16
    x= - 9/5
    x =- 1.8

    Is this correct. I am trying to make sure I am in the right direction

    Also is f(x) = 2x^2-2x
    f(0) = I got )
    f(-1) I got 4
    f(2) Igot 4

    Is this correct also..

    I need to make sure that this one is correct also

    What is the domain of g(x) = 3/5-3x
    I got that x is not equal to 5/3.

    I hope I got all these right...
    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. May 23, 2009 #2
    I think you have a typo for f(0), what did you get? I agree with your answer for f(-1) and f(2). If part 1 has the x upstairs in the fractions like,
    (5*x)/8 + (1*x)/16 = 9/16 + x
    then I agree with your answer. But not if it is downstairs like,
    5/(8*x) +1/(16*x) = 9/16 +x

    I'm not sure I agree with your domain of g(x). What is your reasoning for 5/3?
  4. May 23, 2009 #3
    Because I can not see g(x) = 3/5-3x answers being either a.not equal to 3, b. equal to 0. or c x greater than or equal to 5/3..My head is spinning numbers maybe Im wrong

    and for f(0) = 2x^2 -2x when you mutiply be zero the answer is 0..right?
  5. May 24, 2009 #4
    The problem with the domain question is that we were not sure if you meant
    [tex]g(x) = \frac{3}{5 - 3x}[/tex]
    [tex]g(x) = \frac{3}{5} - 3x.[/tex]

    It looks like you meant the former. (That is why it's helpful to learn LaTex. :wink:) Anyway, you're right -- the domain is
    [tex]x \neq \frac{5}{3}.[/tex]

  6. May 24, 2009 #5
    I have a some more problems that I want checked will you be willing to look at them, please.
  7. May 26, 2009 #6


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    Homework Helper

    Just post them in a new thread. Also, if you're seriously unsure whether your answer is correct or not, point out which steps you weren't sure about when you were solving the question.
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