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    Math whiz?

    My son is taking college algebra and he has a problem that I just can't seem to figure out. (I hate math!)

    -5X^2 +17X +20

    Factoring USED to be the one thing I was good at but it has been more years that I care to admit.

    #2
    nevermind. I wasnt thinking

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      #3
      That gives me a headache just looking at it. I can barely remember the order of operations and to balance the equation. I can not however remember how to do it all though....

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        #4
        Pi R round, Cornbread R Square

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          #5
          Are you wanting it factored?

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            #6
            yes. As far as I can tell it isn't possible to factor with these numbers.

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              #7
              Google Quadratic Formula

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                #8
                use the quadratic equation to solve. x=​(−b±√(​b​2​​−4ac​​​​​))/2a

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                  #9
                  If it's asking to solve by factoring, it cant be done with rational numbers. In other words, "there are no like terms". That 17 is trouble factor-wise. Maybe a mistype? If it's asking to solve with the quadratic formula, it gets some funky numbers as well.

                  Quad Formula: x = {-b +/- [sqrt(b^2 - 4ac)]} / 2a

                  where ax^2+ bx + c = 0.

                  Solve for both X's (+/-) and plug into original formula.?

                  Someone correct me if i'm wrong. A bit rusty.

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                    #10
                    You can't really factor this completely but...
                    Take the x out and get x(-5x+17) + 20

                    or..

                    (5x-2)(-x+3) + 26

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                      #11
                      Quadratic formula is if the equation is equal to 0. This equation is not equal to 0 and you are not solving for x. Just simply factoring.

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                        #12
                        My TI-89 tells me "Too few arguments"! What are you solving for?

                        If it's factoring...
                        -(5x^2-17x-20)
                        Last edited by jlinville; 07-17-2017, 12:57 PM.

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                          #13
                          what's the problem?

                          If you set it equal to zero the roots are 4.32 & -0.92.

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                            #14
                            Graph it and find the 2 points it crosses the X-Axis. Those 2 points are the "zeros" of the factor and function.

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                              #15
                              Originally posted by dbenn454 View Post
                              You can't really factor this completely but...
                              Take the x out and get x(-5x+17) + 20

                              or..

                              (5x-2)(-x+3) + 26
                              This is the answer the Professor wants. In either that form or like this since it is more refined (5x-2)(3-x) + 26 = -5x^2 +17x + 20

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