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Homework Help: Intersections math problem

  1. Sep 27, 2004 #1
    how wud i do the following:

    1.ax+by=c, y=2ax
    2.y=mx+c, y=-mx+d
    3.ax-by=1, y=x
    4.some values for a,b and c for which equation does not represent a straight line, give egs

    ive dun simpler versions of 1-3 but i haven't come across the above, so cud someone please tell me a simple method of working them out. thnx
  2. jcsd
  3. Sep 27, 2004 #2
    I'm having trouble understanding what you want. Are you trying to solve all six equations simultnaeously? 5 unknowns for 6 equations means you have a dependent equation in that lot. What class is this for? Linear Algebra requires a slightly diffferent approach than regular algebra. Do you know how to use matrices?

    Anyway, a little more information presented slightly more clearly would help here.
  4. Sep 28, 2004 #3
    all the questions are separate, hence the numbering of each question. its as level and ive jut started this work so i need a bit of help
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