Solve the System of Equations Using Substitution $$\left\{ \begin{array} { l } x y = 20 \\x + y = 9\end{array} \right.$$

Multiple Choice

Solve the system of equations using substitution.
- $$\left\{ \begin{array} { l } x y = 20 \\x + y = 9\end{array} \right.$$

A) $x = 6 , y = 3 ; x = 3 , y = 6$
B) $x = 10 , y = 2 ; x = 2 , y = 10$
C) $x = 5 , y = 4 ; x = 4 , y = 5$
D) $x = 20 , y = 1 ; x = 1 , y = 20$