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    wjen you get a simultaneous equation like:
    x^2 + y^2 = 29
    x - y = 4
    how would you work it out it was one of the exam question in the November 2003 maths exams i need a genius or some one who know it to help my
    thanks in advance

    V
    BTW if you do decide to help me tehn could you please make it as simple as possible :P thanks again
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    (Original post by vmong)
    wjen you get a simultaneous equation like:
    x^2 + y^2 = 29
    x - y = 4
    how would you work it out it was one of the exam question in the November 2003 maths exams i need a genius or some one who know it to help my
    thanks in advance

    V
    BTW if you do decide to help me tehn could you please make it as simple as possible :P thanks again
    Take the second equation and make either x or y the subject:

    x = y + 4

    Now substitute this into the first equation:

    (y + 4)^2 + y^2 = 29

    Expand the bracket:

    y^2 + 8y + 16 + y^2 = 29

    2y^2 + 8y - 13 = 0

    Solve that quadratic to get values for y, then substitute each of these into x - 4 = 4 to get the x values.
 
 
 
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