1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Algebra 2 homework questions

  1. May 20, 2009 #1
    1. The problem statement, all variables and given/known data
    I have five questions on some review problems for our final I was given and I have forgotten how to do them. They are:
    1) 3(sqrt(5-x)+1)-7=sqrt(5-x)+6
    2) 2(64^x-2)=8(.25)^x+1
    3) x-2-(4-x^2/x+2)=3x+7

    2. Relevant equations
    None that I can think of

    3. The attempt at a solution
    For #3 I have gotten it down to x=4x^2+15x+22, but this makes little sense and all of the other ones I have no clue on how to do them.

    Thank you
  2. jcsd
  3. May 20, 2009 #2


    User Avatar
    Homework Helper

    You solve a quadratic equation by using the ABC formula or by factorization. That said the expression you've gotten for #3 is wrong. Please show how you got there.

    Edit: Show us some work for all problems.
    Last edited: May 20, 2009
  4. May 21, 2009 #3


    Staff: Mentor

    You weren't clear on what you're supposed to do with these problems. Problems 1, 2, and 3 are equations, so presumably you're supposed to solve them--i.e., find values of x that make them true statements. Problems 4 and 5 are expressions, so presumably you are supposed to simplify them.

    Several of your problems are ambiguous due to the lack of parentheses. For example, in 2, you wrote 64^x-2. Is this 64x - 2 or is it 64x - 2? If it's the latter, without LaTeX, it should be written as 64^(x - 2).

    For 3, which you wrote as 4-x^2/x+2, I suppose you meant (4 - x2)/(x + 2) rather than 4 - x2/(x + 2) or 4 - x2/x + 2. All three of these have different values.

    For 4, you have both A and a. Are these different variables? Also you have -2A^-2. Is this (-2A)-2 or the negative of 2A-2? These are different values.

    For 5, you have 3x^2y^7z^-2/12xy^8z^5. My best guess is that you meant this as
    [tex]\frac{3x^2y^7z^{-2}}{12xy^8z^5}[/tex], but what you wrote could reasonably be interpreted in a number of other ways, all with different values.

    One way to write these so that their meaning is clear is to write them using the LaTeX tags. Another way is to use parentheses to clearly separate numerators and denominators in rational expressions and to mark the base and exponent on exponential expressions. Also, a space added between two factors in a product of exponential expressions makes it easier to understand what you have written.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook