1. Not finding help here? Sign up for a free 30min 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!

Algebra Help

  1. Dec 23, 2009 #1
    1. The problem statement, all variables and given/known data

    Ok this was a physics problem...

    I'm having a hard time with the algebra part

    2. Relevant equations

    solve for X

    7.35E22/(3.84403E8 - X)^2 = 5.98E24/X^2

    3. The attempt at a solution

    i have got down to this and I think it is right but it might be wrong

    0 = (7.35E22 X^2)/5.98E24 - X^2 + 2(3.84403E8)X - (3.84403E8)^2
     
  2. jcsd
  3. Dec 23, 2009 #2

    Mentallic

    User Avatar
    Homework Helper

    Rather than dealing with all those long and annoying numbers, lets assign letters to stand for them, and we can substitute back after all the algebra is done.

    Let:
    [tex]A=7.35x10^{22}[/tex]
    [tex]B=3.84403x10^8[/tex]
    [tex]C=5.98x10^{24}[/tex]

    So now we have [tex]\frac{A}{(B-X)^2}=\frac{C}{X^2}[/tex]

    You want to get rid of the fractions, so you need to multiply by the higher common factor, which is [itex]X^2(B-X)^2[/itex]

    Then you'll get [tex]AX^2=C(B-X)^2[/tex]

    Now you need to expand, move everything to one side and let the equation = 0 and collect like terms. You should get it in the form [itex]mx^2+nx+p=0[/itex] where m, n and p are all some constant, and x is the variable that you're trying to solve.

    Now you can apply the quadratic formula.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Algebra Help
  1. Algebra help (Replies: 1)

  2. Algebra help (Replies: 7)

  3. Help with Algebra (Replies: 15)

  4. Algebra help (Replies: 6)

  5. Algebra Help (Replies: 2)

Loading...