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Math Help - X, Y value problem

  1. #1
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    X, Y value problem

    Dear Group Members,

    Can anyone help me to find out value of X & Y.

    X + √y = 21
    √x + y = 29

    Thanks.
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  2. #2
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    Hi.

    Quote Originally Posted by yegparkash View Post
    Dear Group Members,

    Can anyone help me to find out value of X & Y.

    X + √y = 21
    √x + y = 29
    Do you know this method:

    Cramer's rule - Wikipedia, the free encyclopedia

    ?

    Yours
    Rapha
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  3. #3
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    Quote Originally Posted by yegparkash View Post
    Dear Group Members,

    Can anyone help me to find out value of X & Y.

    X + √y = 21
    √x + y = 29

    Thanks.

    Rearrange & square the 2nd equation

     \sqrt{x} + y = 29
    rearranged
     \sqrt{x} = 29 - y

    squared
     x = (29 - y)^2

    replace x in equation
     (29 - y)^2 + \sqrt{y} = 21

    You have 1 equation & 1 unknown

    .

    NOTE:
    The sum of 2 irrational numbers is an irrational number.
    For this specific problem, the square root of x & square root of y
    must be natural numbers.
    Last edited by aidan; September 4th 2009 at 11:57 PM. Reason: added note
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  4. #4
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    Quote Originally Posted by Rapha View Post
    Hi.



    Do you know this method:

    Cramer's rule - Wikipedia, the free encyclopedia

    ?

    Yours
    Rapha
    Cramer's Rule can only be used for a system of linear equations. The posted system is NOT linear.
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