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Math Help - Help with inequalities

  1. #1
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    Help with inequalities

    Yes, it's me again and I need more help. This time I couldn't do anything with this problem because I really did not understand this one. Here is the problem: (x+6)(x-16)(x+5)>0; The solution set is (xl ).
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  2. #2
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    Quote Originally Posted by lizann View Post
    Yes, it's me again and I need more help. This time I couldn't do anything with this problem because I really did not understand this one. Here is the problem: (x+6)(x-16)(x+5)>0; The solution set is (xl ).
    Draw a graph of y = (x+6)(x-16)(x+5). For what values of x is it above the x-axis (that is, y > 0)?
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  3. #3
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    Make the following table:





    • In the first column, identify the factors and the expression that you want to analize.
    • Following up on this, find where the expressions get zero and identify every interval as it's written above.
    • Pick a number of the interval and substitute it into the factors to see the sign in such interval.
    • Finally multiply vertically to see the sign of the whole expression.


    We require the positive sign, so the solution set is S=(-6,-5)\cup (16,\infty ).
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  4. #4
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    Thank you

    Thanks for the help very much appreciated.
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