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    x^2 - y^2 =14
    xy = 24
    What’s x and y equal to? Why my teacher says there are no real roots?
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    (Original post by XchickenX)
    x^2 - y^2 =14
    xy = 24
    What’s x and y equal to? Why my teacher says there are no real roots?
    x^2=14+y^2 and from eq (2) we get that x^2y^2 = 576. Sub the prev. one in (14+y^2)y^2 = 576 which yields a quartic, which is a disguised quadratic, of y^4+14y^2-576=0. This indeed has two real roots, and hence you can find their x counterparts via eq (2)
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