Give All Solutions of the Nonlinear System of Equations, Including $$\begin{array} { l } x ^ { 2 } + y ^ { 2 } = 90 \\x ^ { 2 } - y ^ { 2 } = 72\end{array}$$

question 373

Multiple Choice

Give all solutions of the nonlinear system of equations, including those with nonreal complex components.
- $$\begin{array} { l } x ^ { 2 } + y ^ { 2 } = 90 \\x ^ { 2 } - y ^ { 2 } = 72\end{array}$$

• A) \(\{ ( 9,3 ) , ( 3,9 ) , ( - 9 , - 3 ) , ( - 3 , - 9 ) \}\)
• B) \(\{ ( 9 , - 3 ) , ( 9,3 ) \}\)
• C) \(\{ ( - 9 , - 3 ) , ( - 3 , - 9 ) \}\)
• D) \(\{ ( 9,3 ) , ( - 9,3 ) , ( 9 , - 3 ) , ( - 9 , - 3 ) \}\)

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