I need help with a math problem =P

Discussion in 'Off Topic' started by B1gB1rd09, May 31, 2009.

  1. B1gB1rd09

    B1gB1rd09 Ancient
    Senior Member

    Messages:
    43
    Likes Received:
    0
    Alright, I'm supposed to solve for x.

    1-1=1+2
    x c d x

    Thanks in advance!
     
  2. Nick Novikov

    Nick Novikov Ancient
    Senior Member

    Messages:
    792
    Likes Received:
    0
    Don't we have schools for this?
     
  3. EpicFishFingers

    EpicFishFingers Ancient
    Senior Member

    Messages:
    2,887
    Likes Received:
    6
    I don't get it

    1-1 =/= 1+2

    do you want us to substitute in the x's and c's and d's? And if so, where?
     
  4. B1gB1rd09

    B1gB1rd09 Ancient
    Senior Member

    Messages:
    43
    Likes Received:
    0
    The c's,d's, and x's are part of a fraction with the number (there in the denominator) above them, however my post screwed it up =P.

    And yes we have schools for this, but my teacher isn't the best in the world.
     
  5. soccerlax13

    soccerlax13 Ancient
    Senior Member

    Messages:
    10
    Likes Received:
    0
    So, 1/x-1/c=1/d+2/x?

    I'm currently trying (and failing) to focus on my own math homework, but the way you'd go about doing that is getting a least common denominator on each side.
     
  6. Blep1337

    Blep1337 Ancient
    Senior Member

    Messages:
    61
    Likes Received:
    0
    hmmm...i dont remeber how to do this
     
  7. What's A Scope?

    What's A Scope? Ancient
    Senior Member

    Messages:
    3,285
    Likes Received:
    21
    This the equation, correct?

    Code:
    1/x - 1/c = 1/d + 2/x
    Put the x's on the same side and everything else on the other.

    Code:
    - 1/c - 1/d = 1/x
    or
    Code:
    1/x = -1/c - 1/d
    This is as far as I can get while being sure.
    Next is what I think.

    Multiply everything by x^2 (x squared).
    Code:
    x = -1x^2/c - 1x^2/d
    That doesn't seem right to me, but that's the best I can do. I'll keep trying.
     
  8. jpitty

    jpitty Ancient
    Senior Member

    Messages:
    267
    Likes Received:
    0
    I think it is Undefined.


    Or maybe its

    X = -(CD/(C+D)
     
    #8 jpitty, Jun 1, 2009
    Last edited: Jun 1, 2009
  9. X5

    X5 Ancient
    Senior Member

    Messages:
    2,277
    Likes Received:
    0
    Uhm... I am having trouble. Am I confused, or is everyone that far off? To get rid of fractions, you don't square the denominator, and it isn't undefined simply because there are more than 1 variable. It just means the solution for X is not a constant.

    Code:
     1/x - 1/c = 1/d + 2/x 
    Subtract 2/x from both sides, and add 1/c to both sides.

    Code:
     1/x - 2/x = 1/d + 1/c 
    Code:
     -1/x = 1/d + 1/c 
    Now make 1/d and 1/c have common denominations by multiplying both sides by c/c and d/d (both equal 1, so it won't affect the x side of the equation). Then add the right side.

    Code:
     -1/x = c/dc + d/dc 
    Code:
     -1/x = c+d/dc 
    Now you need to get x out of the fraction. So, multiply both sides of the equation by x (do not multiply x into the right side, this would only be an extra un-needed step).

    Code:
     -1 =  (c+d/dc) (x) 
    However, x needs to be alone on a single side of the equation. So, multiply both sides by (dc/c+d) [note that this will cancel out with c+d/dc making it 1x or just x on the right side].

    Code:
     (-1) (dc/c+d) = x 
    Now distribute the negative, and lets flip left side with right side so that x is on the left side of the = sign.

    Code:
     x = -dc/c+d 
    There you have it, basic algebra (unless I am making some huge mistake here... in which case fuuuuuuuuuu)

    Edit: Okay, Jpitty fixed himself.
     
  10. jpitty

    jpitty Ancient
    Senior Member

    Messages:
    267
    Likes Received:
    0

    Okay ya, I thought I was alone. I had to go redo it because it just didn't seem right, and if we both got the same answer, it has to be right....right?
     
  11. X5

    X5 Ancient
    Senior Member

    Messages:
    2,277
    Likes Received:
    0
    If I got an answer it is right... because I am right. Always.
    /ego
     
  12. jpitty

    jpitty Ancient
    Senior Member

    Messages:
    267
    Likes Received:
    0
    Okay, Chuck Norris.
     
  13. V

    V Ancient
    Senior Member

    Messages:
    711
    Likes Received:
    0
    The second to last pic is wrong. You divide by (c+d/cd), not multiply by it. If you wanna cancel a variable/number in a multiplication sequence (as is the case with [x] [c+d/cd]) you have to divide both sides by one of those variables/numbers. It should read:
    Code:
     (-1) / (c+d/cd) 
    Which can be simplified by into.....oh my god......haha wow I just failed miserably. I end up getting the same answer you did sweeny. *facepalm
     
    #13 V, Jun 1, 2009
    Last edited: Jun 1, 2009
  14. EpicFishFingers

    EpicFishFingers Ancient
    Senior Member

    Messages:
    2,887
    Likes Received:
    6
    Wow, this is onl;y basic maths. We're all overcomplicating things. What year/grade are you in, OP?

    This could probably accomplished at GCSE level.
     

Share This Page