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Grrrr Help would be appreciated

  1. Jan 26, 2006 #1
    for each of the following, find a point on each line:

    x=5

    :D LOl ok this is what i thought

    x+0y-5=0

    so direction vector=(0,1)

    If I set x to 5 then y should = 0 shouldn't it?
     
  2. jcsd
  3. Jan 26, 2006 #2
    First think about what would happen if you didn't set x equal to 5, say you set x equal to 6 what happens?

    You don't set x equal to 5, x is 5 period end of story, that is what you're given all points on that line are of the form (5,a) where a is any real number. You just need one point, I think you can figure it out from here.
     
  4. Jan 26, 2006 #3
    yea I just saw at the back of the book it said (5,6) and I had no idea where that came from
     
  5. Jan 27, 2006 #4

    HallsofIvy

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    READ the problem! It said "find a point on each line". How many points are there on a line? Since the equation is x= 5, obviously the first coordinate must be 5. What about the second coordinate? What does that equation tell you about y? How does that equation restrict y?

    Your answer, (5, 0), is a perfectly good answer. So is (5, 6). So is
    (5, 323121232344).
     
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