Results 1 to 6 of 6

Math Help - Can someone help me please

  1. #1
    key
    key is offline
    Newbie
    Joined
    Sep 2007
    Posts
    21

    Can someone help me please

    I need help with these two problems

    |2x+3|> -14

    |6-2x| > -10

    Can someone tell me exactly why these are no solution

    Sorry this should be in inequalites
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor red_dog's Avatar
    Joined
    Jun 2007
    From
    Medgidia, Romania
    Posts
    1,252
    Thanks
    5
    Quote Originally Posted by key View Post
    Can someone tell me exactly why these are no solution
    On the contrary, they have as solution any real number.
    Because |a|\geq 0, \forall a\in\mathbf{R}
    Follow Math Help Forum on Facebook and Google+

  3. #3
    key
    key is offline
    Newbie
    Joined
    Sep 2007
    Posts
    21
    i am still confused
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor red_dog's Avatar
    Joined
    Jun 2007
    From
    Medgidia, Romania
    Posts
    1,252
    Thanks
    5
    |2x+3|\geq 0>-14, \ \forall x\in\mathbf{R}
    So the inequality is true for any real x.
    Follow Math Help Forum on Facebook and Google+

  5. #5
    key
    key is offline
    Newbie
    Joined
    Sep 2007
    Posts
    21
    ok thanks but what if the problem was |2x+3}< -14
    would it then be no solution
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Math Engineering Student
    Krizalid's Avatar
    Joined
    Mar 2007
    From
    Santiago, Chile
    Posts
    3,654
    Thanks
    13
    Apply the absolute value definition

    f(x)=|x|=\left\{\begin{array}{cc}x&\text{if }x\ge0\\<br />
-x&\text{if }x<0\end{array}\right.
    Follow Math Help Forum on Facebook and Google+


/mathhelpforum @mathhelpforum