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Another problem that I guessed right.

  1. Jan 2, 2007 #1
    -_- I'm getting annoyed and I suppose that you guys are too of problems that I don't know exactly how it works!! I've made educated guesses and apparently have guessed this one right.

    Here goes:
    If 2lx+3l=4 and ly+1l/3=2, then lx+yl could equal each of the following EXCEPT:

    a) 0
    b) 4
    c) 8
    d) 10
    e) 12
  2. jcsd
  3. Jan 2, 2007 #2
    Oops, the correct answer is D and I think this is because the other numbers are divisble by 4 and 2 except 10?? lol Can anyone tell me a way of solving this numerically? Plug in numbers? solve for x and y? Please also state the way you think is most efficient. Thanks!
  4. Jan 2, 2007 #3
    Solve for x in both expressions. Since you have an absolute, there is 2 solutions to each expression. There is a total of 4 combinations for x + y, find all of them and deduce which answer is wrong. And by the way, why don't you make a thread where you can post all your questions? No need to make 3 threads. :tongue2:
    Last edited: Jan 2, 2007
  5. Jan 2, 2007 #4
    haha ok, yeah I solved it thanks!!
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