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    • Thread Starter
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    I've got two questions that i have done but the answers in the back of the book say i'm wrong:
    1. |4-x| < 2

    For this I got 8<x<2 which is obviously wrong because x can't be greater than 8 but less than 2. The book says 2<x<6.

    my calculations were as follows: -2<4-x<2
    -8<-x<-2
    8<x<2
    I'm sure i've made some stupid mistake somewhere!

    2. |2x-3|<|4+x|

    For this i got x<-1/3 or x<7

    The book says -1<x<7/3

    Any help is much appreciated!
    • Community Assistant
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    Question 1

    When you subtract 4 from -2 you do not get -8.

    When you multiply by a negative number, the direction of the inequality changes.

    Question 2

    Show some working. The first step is to square both sides.
    • Thread Starter
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    see stupid mistakes! i did it all in class in a rush. i've got it now. thanks!
    • Community Assistant
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    good
 
 
 
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