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Math Help - linear inequalities ..checking answer

  1. #1
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    linear inequalities ..checking answer

    hi-
    i have to slove this problem

    -3/2x > -6

    what i did was i multiply 2 to -3/2 and -6
    i cancel the 2 and i got -12

    so i am left with -3x>-12
    i then divide -3 to both sides. and i got

    4>x
    is this correct?

    thanks
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  2. #2
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    Quote Originally Posted by Candy101 View Post
    hi-
    i have to slove this problem

    -3/2x > -6

    what i did was i multiply 2 to -3/2 and -6
    i cancel the 2 and i got -12

    so i am left with -3x>-12
    i then divide -3 to both sides. and i got

    4>x
    is this correct?

    thanks
    yes, x < 4
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  3. #3
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    Am I suppose to change the sign from > to < becuase I divided by a negative number? So the
    answer will be x<4?
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  4. #4
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    No, you did that when you swapped the sides!

    You had -3x> -12. If you had simply divided both sides by -3 without either changing the sign or swapping sides you would have x> 4 which would be wrong. You can either change the sign, to get x< 4 or swap sides to get 4> x (your answer) but not both.

    Of course, it is easy to check this yourself. A number less than 4 is 2. Does x= 2 satisfy (-3/2)x> -6?
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