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Math Help - Signed 6

  1. #1
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    Signed 6

    In solving
    -7x + x = 24 -x

    x = - 4

    Where do we get the 6?


    -7x + x = 24 - x + x somehow this line produces a six for -6x = 24
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  2. #2
    is up to his old tricks again! Jhevon's Avatar
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    Quote Originally Posted by radioflyer01 View Post
    In solving
    -7x + x = 24 -x

    x = - 4

    Where do we get the 6?


    -7x + x = 24 - x + x somehow this line produces a six for -6x = 24
    -7x + x = -6x

    since we started with -7x's and we added one x to it, so we have one more than -7x's now, which is -6x

    this is wrong however, you should add x to both sides:

     -7x + x = 24 - x

    \Rightarrow -7x + x + x = 24 - x + x ......add x to both sides

    \Rightarrow -5x = 24

    \Rightarrow x = - \frac {24}{5}
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  3. #3
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    So, one more than -7x's equals 6x instead of eight x?

    -7x = 24 -x

    -7x = 24 + -1x

    Adding x

    -7x + x = 24 + -1x + x

    -7x + x = somehow equals -6x instead of eight x.

    -6x = 24 + -1x + x

    -1x + x = 0

    -6x = 24 + 0

    -6x = 24

    x = -4
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  4. #4
    is up to his old tricks again! Jhevon's Avatar
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    Quote Originally Posted by radioflyer01 View Post
    So, one more than -7x's equals 6x instead of eight x?

    -7x = 24 -x

    -7x = 24 + -1x

    Adding x

    -7x + x = 24 + -1x + x

    -7x + x = somehow equals -6x instead of eight x.

    -6x = 24 + -1x + x

    -1x + x = 0

    -6x = 24 + 0

    -6x = 24

    x = -4
    so the original equation was -7x = 24 - x?

    ok. obviously you're having trouble adding -7 and + 1

    -7 + 1 = -6, not 8. if you can't see this, rearrange it, put the +1 in front. we get:

    1 - 7 = ? obviously the answer isn't 8! it's -6

    if you still don't see it, draw it on a number line. if you start at the point labeled -7 and move 1 unit in the positive direction, you will end up at -6

    -7x = 24 - x

    \Rightarrow -7x + x = 24 - x + x

    \Rightarrow x - 7x = 24

    \Rightarrow -6x = 24

    \Rightarrow x = - \frac {24}{6}

    \Rightarrow x = -4
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