More systems of quadratics...

[b_ball_chic]

Sorry guyz...one last question...

x^2 - 5y^2 = -44
xy = -24
divide by x: y = -24/x
substitute:
x^2 - 5(-24/x)^2 = -44
multiply: x^2 - 2880/x = -44

Where do I go from here?? :uhh:

[dextercioby]

Sorry guyz...one last question...

x^2 - 5y^2 = -44
xy = -24
divide by x: y = -24/x
substitute:
x^2 - 5(-24/x)^2 = -44
multiply: x^2 - 2880/x = -44

Where do I go from here?? :uhh:

Wrong,u should get a biquadratic.
x^{2}-\frac{2880}{x^{2}}=-44

Can u solve this type of equations...??
HINT:plug
x^{2}=t

And solve the quadratic equation...

Daniel.

[Hurkyl]

x^2 - 5(-24/x)^2 = -44
multiply: x^2 - 2880/x = -44

This is wrong.


As a further technicality, your logic thus far shatters when you consider the possibility that x = 0: you have to do one of three things:

(1) avoid dividing by x
(2) handle x = 0 as a special case
(3) prove x = 0 cannot happen