$$\left. \begin{array} { l } { x = x y } \\ { \frac { 3 ( c ^ { 2 } + 4 ) ( ) } { 0 ( a ^ { 2 } , 0 , 0 ) } - r ^ { 2 } \right.$$
$\left\{\begin{matrix}\\x=0\text{, }&\text{unconditionally}\\x\in \mathrm{C}\text{, }&y=1\end{matrix}\right.$
$\left\{\begin{matrix}\\x=0\text{, }&\text{unconditionally}\\x\in \mathrm{R}\text{, }&y=1\end{matrix}\right.$
