HI! Actually I have no idea of how to solve this problem, could any one help me please? (Clapping) You have to find de values for A, B and C.

Attachment 18211

Thanks

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- Jul 15th 2010, 07:24 PMIssokaEquations problem
HI! Actually I have no idea of how to solve this problem, could any one help me please? (Clapping) You have to find de values for A, B and C.

Attachment 18211

Thanks - Jul 15th 2010, 08:06 PMProve It
You have

$\displaystyle \begin{cases}x + y + z = 3 \\ x^2 + y^2 + z^2 = 9 \\ xyz = -2\end{cases}$

From equation 1:

$\displaystyle x = 3 - y - z$, so

$\displaystyle \begin{cases}(3 - y - z)^2 + y^2 + z^2 = 9\\ (3 - y - z)yz = -2\end{cases}$

$\displaystyle \begin{cases}(3 - y - z)^2 + y^2 + z^2 = 9 \\ zy^2 + (z^2 - 3z)y - 2 = 0\end{cases}$

Since the final equation is now a quadratic in $\displaystyle y$, you can solve for $\displaystyle y$ in terms of $\displaystyle z$ using the quadratic formula.

Everything else should piece together after that.