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Equation of a plane

  1. Dec 15, 2009 #1
    1. The problem statement, all variables and given/known data
    write the equation of the plane that contains the point(-1, 2, -2) and satisfies
    1. parallel to xy plane
    2. orthogonal to z-axis
    3.parallel to both the x and z axes
    4. parallel to the plane x-y+3z = 100 (plane A)

    2. Relevant equations

    3. The attempt at a solution
    i started with finding the normal of plane A which is <1,-1,3>
    and i know that the normal of this plane should be the normal of my plane suince they're
    but what i don't get is how the plane im finding can be orthogonal the the z axizs and parallel to it at the same time...
    i drea it and it still doesn't look like it makes sense
    i don't know where to go from here...
  2. jcsd
  3. Dec 15, 2009 #2


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    Homework Helper

    Are you sure you don't need to find planes for each of the conditions? I don't think there is a single plane that satisfies all of those conditions.
  4. Dec 15, 2009 #3


    Staff: Mentor

    The first two equations are equivalent. A plane that is parallel to the x-y plane is automatically orthogonal to the z-axis.
  5. Dec 15, 2009 #4
    now that i think of it...i think i was supposed to find ones that satisfy each.
    wow i feel dumb
    i was actually stressing about how a plane could bend to meet the reqs :s
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