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Math Help - A number puzzle for u

  1. #1
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    Question A number puzzle for u

    There are two numbers with the difference of 3 between them and the difference of their squares is 51.
    Can you find the numbers???
    Last edited by mr fantastic; October 11th 2009 at 06:27 PM. Reason: Removed link that promotes commercial website
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  2. #2
    MHF Contributor Bruno J.'s Avatar
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    Spoiler:
    Suppose the two numbers are a and b, with a<b.

    Then the problem says that b-a=3 and b^2-a^2=51. Note that b^2-a^2=(b-a)(b+a). Can you finish now?
    Last edited by mr fantastic; October 11th 2009 at 06:30 PM.
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  3. #3
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    Quote Originally Posted by Bruno J. View Post
    Suppose the two numbers are a and b, with a<b.

    Then the problem says that b-a=3 and b^2-a^2=51. Note that b^2-a^2=(b-a)(b+a). Can you finish now?
    I suspect the OP was meant to be a challenge question (which is why the thread was moved to here and why I put spoiler tags around your reply).
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  4. #4
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    @ Bruno: yes you are right,,,

    But No answers yet??
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  5. #5
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    Quote Originally Posted by mr fantastic View Post
    I suspect the OP was meant to be a challenge question (which is why the thread was moved to here and why I put spoiler tags around your reply).
    Then why post his solution immediately below?
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  6. #6
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    Thumbs up

    X = 10
    y = 7
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  7. #7
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    Quote Originally Posted by HallsofIvy View Post
    Then why post his solution immediately below?
    I didn't want to delete the reply on the one hand but I didn't want the reply to be in plain sight on the other hand. So my third hand decided a good compromise would be to put spoiler tags around it.
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  8. #8
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    Quote Originally Posted by mr fantastic View Post
    So my third hand decided a good compromise would be to put spoiler tags around it.
    Is 3 hands what makes you "fantastic"?
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