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Math Help - can you answer this?

  1. #1
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    can you answer this?

    I know the answer to this problem - I just don't know how they got this answer:

    5{3 to the 2nd power - 4[8 +(2 to the 3rd power - 18 divided by 2 times 3)]}
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  2. #2
    Forum Admin topsquark's Avatar
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    Quote Originally Posted by Reesa View Post
    I know the answer to this problem - I just don't know how they got this answer:

    5{3 to the 2nd power - 4[8 +(2 to the 3rd power - 18 divided by 2 times 3)]}
    I am guessing here. Is this what you mean?
    5^{3^2 - 4 \left [8 + \frac{2^3 - 18}{2 \cdot 3} \right ] }

    This is what you wrote:
    5^{3^2 - 4 \left [ 8 + 2^3 - \frac{18}{2} \cdot 3 \right ] }

    -Dan
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  3. #3
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    Quote Originally Posted by Reesa View Post
    I know the answer to this problem - I just don't know how they got this answer:

    5{3 to the 2nd power - 4[8 +(2 to the 3rd power - 18 divided by 2 times 3)]}
    The trouble here is writing clearly. It is very, very difficult to convey exactly what is meant.

    If you mean this:

    5*(3^{2}-4(8+(2^{3}-18/2*3)))

    Just one piece at a time. Keep in mind ALL the rules concerning the order of operations.

    5*(3^{2}-4(8+(2^{3}-18/2*3)))
    Exponents
    5*(9-4(8+(8-18/2*3)))
    Parentheses from Inside to Outside
    Multiplication or Division Before Addition or Subtraction
    Left to Write when no other rule prevails
    5*(9-4(8+(8-9*3)))
    5*(9-4(8+(8-27)))
    5*(9-4(8+(-19)))
    5*(9-4(8-19))
    5*(9-4(-11))
    5*(9+44)
    5*53
    265

    Again, if I have not decode the original expression correctly, I just got the wrong answer. Great care must be taken.
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  4. #4
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    can no one help?

    Did anyone get the problem?
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  5. #5
    is up to his old tricks again! Jhevon's Avatar
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    Quote Originally Posted by Reesa View Post
    Did anyone get the problem?
    i think they are waiting on you to clarify what the question was. what you typed was not completely understandable, everyone has to be guessing at what you meant. please clarify
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  6. #6
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    You got the right answer!

    Can you please explain the problem from 5(9-4(-11))

    Thank YOU!!!
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  7. #7
    Forum Admin topsquark's Avatar
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    Quote Originally Posted by Reesa View Post
    Can you please explain the problem from 5(9-4(-11))

    Thank YOU!!!
    5(9 - 4(-11)) = 5(9 + 44) = 5(53) = 265

    -Dan
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  8. #8
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    It is a little tricky where you are asking. That negative sign in front of the four can be a bit confusing.


    I suspect it is not confusing at all by itself.

    -4(-11) = +44

    However, when written as part of something else, that negative sign takes on a double meaning. Not only does it suggest a value is negative, but it indicates subtraction.

    9-4(-11)

    Those who are used to it adeptly transform this

    9 + 44

    Others wonder what happened.

    Try this first

    9 + 4(-11) = 9 + (-44) = 9 - 44

    Now this one

    9 - 4(-11) = 9 - (-44) = 9 + 44

    Think on it until it soaks in. Get a number line and ponder on the direction of movement for addition or subtraction of positive numbers. Then reverse everything and ponder the direction of movement for addition or subtraction of negative numbers.
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