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Straight Lines!

  1. Aug 29, 2012 #1
    1. The problem statement, all variables and given/known data
    Lines li: ix+(i+1)y+(i+2)=0; i=1,2 intersect at___ point?

    2. Relevant equations
    The equation is required at first!

    3. The attempt at a solution
    I am confused!
    How and where should I replace the values of i with 1 or 2?
    This is the first step but i am unable to do....
  2. jcsd
  3. Aug 29, 2012 #2


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    Science Advisor

    You are given "ix+(i+1)y+(i+2)=0; i=1,2". You replace those "i"s by 1 and 2!

    i= 1: 1x+ (1+1)y+ (1+2)= x+ 2y+ 3= 0
    i= 2: 2x+ (2+1)y+ (2+ 2)= 2x+ 3y+ 4= 0
  4. Sep 14, 2012 #3
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