Give All Solutions of the Nonlinear System of Equations, Including $$\begin{array} { l } 3 x ^ { 2 } + 3 y ^ { 2 } = 20 \\6 x ^ { 2 } + 6 y ^ { 2 } = 48\end{array}$$

Multiple Choice

Give all solutions of the nonlinear system of equations, including those with nonreal complex components.
- $$\begin{array} { l } 3 x ^ { 2 } + 3 y ^ { 2 } = 20 \\6 x ^ { 2 } + 6 y ^ { 2 } = 48\end{array}$$

A) $\{ ( 2,2 ) , ( - 2 , - 2 ) \}$
B) $\varnothing$
C) $\{ ( 2,2 ) , ( 2 , - 2 ) , ( - 2,2 ) , ( - 2 , - 2 ) \}$
D) $\{ ( 2 \mathrm { i } , 2 \mathrm { i } ) , ( 2 \mathrm { i } , - 2 \mathrm { i } ) , ( - 2 \mathrm { i } , 2 \mathrm { i } ) , ( - 2 \mathrm { i } , - 2 \mathrm { i } ) \}$