What's Wrong? Q17 (Type 2)

Describe what's wrong with the working and/or answer.
Suggest how it should look like.


9 comments:

  1. In the final answer, 49 should be 7.

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  2. 49 should be written as (7)^2. thus, a is (x+y) and b is 7, and the end result would be (x+y-7)^2 not (x+y+49)^2

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  3. This comment has been removed by the author.

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  4. The error: the '49' haven't been squared to (7)^2

    How it should look like: =(x+y+7)^2

    Sandy and Ruoyu

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  5. (x+y)^2 - 14(x+y) + 49 ≠ (x+y)^2 - 2(7x+7y) + 49
    ≠ (x+y-49)^2

    It is should be... = (x+y)^2 - 2(7x+7y) + (7)^2
    = (x+y-7)^2

    Owen and shawn kit btwfyi.

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  6. Mavis & Qianhui8/17/2011 08:21:00 AM

    Since the format of the statement should be a^2 + 2ab + b^2 , the 49 should be changed to (7)^2 so we can get (x+y)^2-2(7x+7y)+(7)^2
    Answer : (x+y)^2-2(7x+7y)+(7)^2
    = (x+y-7)^2

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  7. M4®k †å¥ & Yi De8/17/2011 08:21:00 AM

    49 should be put as (7)^2 instead of just 49, making the answer (x+y+7)^2

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  8. Matthew and Wei Siew8/17/2011 09:02:00 AM

    Both his/her working and answer is incorrect.
    In the working, it should have been +(7)^2, instead of +49.
    Therefore, b should be 7 and his answer is also incorrect and should have been (x+y-7).

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