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Homework Help: Impossible question HELP NEEDED

  1. Jun 1, 2009 #1
    Impossible question!!! HELP NEEDED

    1. The problem statement, all variables and given/known data

    Find the point of intersection of GE and BH.

    The point of origin will be Point A, the starting point.

    2. Relevant equations

    http://img189.imageshack.us/img189/7720/diagram3.png [Broken]

    The measurements in ft (feet) show the distance between the lettered points. Hint: Treat the diagram like a cartesian plane.

    3. The attempt at a solution

    i don't even know what to do
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Jun 1, 2009 #2


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    Homework Helper
    Education Advisor
    Gold Member

    Re: Impossible question!!! HELP NEEDED

    Find the ordered pair coordinates for each points, B, E, G, and H. Point A, being the origin, is the ordered pair, (0, 0).

    Any two points define a line. You are interested in the intersection of BH and GE. Use the coordinates of BH and of GE to determine their lines (either equations or actually drawing the graph, depending on what works and what is expected). Either solve the system of two equations, or read the point of intersection from the graph.
  4. Jun 1, 2009 #3
    Re: Impossible question!!! HELP NEEDED

    So if A is (0,0) then...

    B = (96, 0)

    E = (299, 0 )

    G = (102, -95)

    H = (204, -95)

    rite? and then I find the slope for line BH and GE which is y2 - y1 / x2 - x1?
  5. Jun 2, 2009 #4


    Staff: Mentor

    Re: Impossible question!!! HELP NEEDED

    You have two different lines that intersect, so (y2 - y1)/(x2 - x1) can't be the slope for both of them. (Note that I put parentheses around the terms in the numerator and around those in the denominator.)

    What you need to do is to find the equation of the line from B to H, and find the equation of the line from G to E. For each one of these you can use the point-slope form of the line, which is y - y0 = m(x - x0). The slope of the line is m, and (x0, y0) is a point on the line.

    After you have found the two equations, find the point of intersection by solving the system of two equations.
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