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    kjhgkhjb
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    Bidmas
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    BODMAS
    You have to multiply/divide before you subtract/add
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    bidmas.
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    To be like everyone else: bidmas

    If you are really new to algebra:
    They are two different equations. In different equations the value of x could be anything, and the objective is to find x. Can you find x in each equation?
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    Algebra is out to spite you.
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    (Original post by addylad)
    To be like everyone else: bidmas

    If you are really new to algebra:
    They are two different equations. In different equations the value of x could be anything, and the objective is to find x. Can you find x in each equation?
    lol, x = times.
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    (Original post by Mr.Pii)
    lol, x = times.
    zomgzlolz :yep:
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    (Original post by ilovefatchicks)
    Please help as I need to progress
    you do:

    3 - (1 x - 4 = -4)
    3 - (-) 4 = 3 + 4 = 7

    negative take negative = postive.

    you times before you add or subtract.
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    (Original post by ilovefatchicks)
    x = times not the the letter x
    omg that confused me soo much... i was sitting there looking at the thread title thinking wtf?
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    I'm not sure, I think you've found a flaw in mathematical theory. :O
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    BIDMAS= brackets, indices, division, multiplication, addition, subtraction. It's the order in which you work out calculations.
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    2 x -4 = -8
    (3-1) x -4 = -8

    3 - 1 x -4 = 7
    3 -(1 x-4) = 7
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    (Original post by ilovefatchicks)
    Please help as I need to progress
    Well, what do you need help with? You've been given the answer.

    We have various conventions we like to uphold in maths, just to make the notation easier and ensure the page isn't full of superfluous symbols. One of these is BIDMAS (or the slightly older BODMAS), standing for "brackets, indices, division/multiplication, addition/subtraction". That is, when you are given a horrible looking expression like "3 - 1 x -4", you should work from left to right, evaluate all the brackets first (there aren't any here), then all the indices (there aren't any here), then all the division and multiplication (1 x -4 = -4, so our expression collapses into "3 - -4", then all the addition and subtraction (and 3 - -4 is just 3 + 4, which is 7), always from left to right. You're not allowed to do the subtraction before the multiplication, which is what you seem to have done.

    If you were given something much nastier like 17 - 4\times 3^2 + 4 \div (3 - 1), the same simple rules apply, you just need to keep a clear head and work through slowly and in order:

    - do the brackets first: 3 - 1 = 2, so our expression becomes 17 - 4\times 3^2 + 4 \div \underline{2}
    - do the indices: 3^2 = 9, so we have 17 - 4\times \underline{9} + 4 \div 2
    - do the multiplication and division from left to right: 4 x 9 = 36, and 4 / 2 = 2, so we have 17 - \underline{36} + \underline{2}
    - and finally, do the addition and subtraction from left to right: 17 - 36 = -19, and -19 + 2 = -17. So our final answer is -17.

    Does that help?
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    Yes you are right! Always wondered that myself.......................... ..
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    I think you will struggle with algebra. I swear they teach this early primary school...
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    (Original post by Chrrye)
    I think you will struggle with algebra. I swear they teach this early primary school...
    .
    Fairly late primary school. And just because the OP didn't pick it up then, doesn't mean they can't now. The fact that they can't do it doesn't necessarily imply that they're stupid, just that they might not have paid attention in school or something - and if I'm honest, I can't blame them, arithmetic is bloody boring.
    • PS Helper
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    Ah, the confusion I had when introduced to Boolean algebra when I found out that A+BC = (A+B)(A+C)...

    That said, I don't think I can give any helpful input to this thread further than what's been said.
 
 
 
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