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Homework Help: I have no idea!

  1. Jan 15, 2005 #1
    Find the x-coordinates of the points on the curve [tex]y=\frac{3x}{2x-3}[/tex] where the normal is parallel to the line 9y=4x+3.

    Could someone tell me what to do?
  2. jcsd
  3. Jan 15, 2005 #2


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    Ask Omicron,apparently he's found a way to solve the same problem.


    P.S.My advice would normally include find the derivative,the equation of the normal and then put the condition of parallelism and find the "x" intercept.
  4. Jan 15, 2005 #3
    Yes, apparently I found a way.
    Find the derivitive
    Gradient of 9y=4x+3 and normal => 4/9
    Gradient of the tangent line => -9/4
    Set -9/4 = derivitive

    You know, its too coincidental that you got the same question as me? :uhh:
    Last edited: Jan 15, 2005
  5. Jan 15, 2005 #4


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    1. What is the slope of the line 9y= 4x+ 3?

    2. What is the slope of a line normal to that?

    3. At what points is the derivative of y(x) equal to the answer you got to 2?
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