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Expert: - 1/25/2011


Question
I'm really Stuck with the following question.
Please help me out if you can.

xy = -24
x^2 + y^2 = 52

Answer
Questioner: Navindra
Country: Sri Lanka
Category: Advanced Math
Private: No
Subject: Quadratic Simultaneous equations
Question: I'm really Stuck with the following question.
Please help me out if you can.
.......................................
xy = -24
x^2 + y^2 = 52

y = - 24/x

x^2 + (-24/x)^2 = 52

x^2 + 24^2/x^2 = 52

x^4 + 24^2 = 52x^2

x^4 - 52x^2 + 24^2 = 0

Solve as a quadratic for x^2, then x = +- the square root of that.

x^4 - 52x^2 + 576 = 0

(x^2 - 36)(x^2 - 16) = 0

You can finish now.

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