System of Equations with Unknown Variables

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The discussion revolves around solving a system of equations involving three variables, x, y, and z. The first equation relates x and y, while the second and third equations incorporate all three variables. The user successfully substitutes y^2 from the first equation into the third but struggles to isolate z. A suggestion is made to treat the equation involving z as a quadratic equation to facilitate isolation. The user expresses gratitude for the advice and plans to try the suggested method.
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Homework Statement



Hello there, I'm having trouble solving the following system:

x^2 + y^2 = 1 (I)

x^2 + z^2 + x*z*sqrt(3) = 4 (II)

y^2 + z^2 + z*y = 3 (III)


Homework Equations





The Attempt at a Solution



Working on (I):

y^2 = 1 - x^2

Working on (III):

(1 - x^2) + z^2 + z*sqrt(1 - x^2) = 3

z = (2 + x^2)/(z + sqrt(1 - x^2))

And here starts the problem, because I can't isolate the 'z', so I can't really move on.
 
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It may look ugly in the end, but to isolate z after you've started working on eqn 3, treat it as a quadratic equation in z.
 
Gib Z said:
It may look ugly in the end, but to isolate z after you've started working on eqn 3, treat it as a quadratic equation in z.

Thank you, I'll try it.
 
I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks
Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
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