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Homework Help: A triangle and a parabola getting romantic! Help me with this please

  1. May 4, 2010 #1
    1. The problem statement, all variables and given/known data
    Here's the problem: refer to question no. 6
    http://img1.uploadscreenshot.com/images/orig/5/12314183569-orig.jpg"


    2. Relevant equations
    I am not sure :S


    3. The attempt at a solution
    This, honestly, is a question which I have no clue how to go about...

    Thanks...
     
    Last edited by a moderator: Apr 25, 2017
  2. jcsd
  3. May 4, 2010 #2

    Mark44

    Staff: Mentor

    Start by drawing the parabola and triangle.
     
    Last edited by a moderator: Apr 25, 2017
  4. May 4, 2010 #3

    LCKurtz

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    Homework Helper
    Gold Member

    All you have to do is figure out the base and height of the triangle. Can you find where the parabola intersects the line? Are there some values of a that don't work? It might help to draw a picture as an example. Try a = 4. Also try a = -1/2.
     
  5. May 4, 2010 #4
    Last edited by a moderator: Apr 25, 2017
  6. May 4, 2010 #5
    okay okay wait wait...

    I solve y=a(squared) and y=9*x(squared) - a --- to get two equations
    Also when x=0 for the parabola, y=-a right?

    Uh okay...could you tell me then what I should do?

    OHHH I made a mistake in the diagram...y is not -0.3 ... y=-3
     
  7. May 4, 2010 #6

    LCKurtz

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    Use the X2 button to do superscripts. So what did you get when you solved

    y = 9x2 - a and y = a2?

    Can you figure out the base of the triangle and its height?
     
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