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Homework Help: Quadractic Equation

  1. Jun 2, 2010 #1
    I have been working on a 2-part question which involves a diagram of a triangle ABC.
    side AC = (2x + 1)
    side BC = (x + 5)
    angle C = 300
    the area of the triangle = 10 cm2

    Question 1
    Find the value of x
    I have done that using the quadratic formula ( x = 2.26)

    Question 2
    Show that: 2x2 + 11x - 35 = 0

    I do not understabnd exactly what I am being asked to do in Qu. 2 and how would I go about answering the question?
     
  2. jcsd
  3. Jun 2, 2010 #2

    HallsofIvy

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    Science Advisor

    Using the quadratic formula on what equation? That is NOT what I got.

    Put the "x" value you got in question 1 on the left side and see what happens. Unfortunately, I don't get that equal to 0 for either your value or mine!
     
  4. Jun 2, 2010 #3

    ehild

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    Homework Helper

    I think the equation in the second question should be 2x2 + 11x - 35 = 0.

    ehild
     
  5. Jun 2, 2010 #4

    Mark44

    Staff: Mentor

    Does the triangle happen to be a right triangle? If it is, that would be good to know. If not, that would be good to know, too.
     
  6. Jun 2, 2010 #5

    HallsofIvy

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    Science Advisor

    If this is were a right triangle, it would be easy to solve for x. And with that value of x, the area would NOT be 10. This cannot be a right triangle.
     
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