Solve the System of Equations Using Substitution $$\left\{ \begin{array} { l } y = x ^ { 2 } - 12 x + 36 \\x + y = 18\end{array} \right.$$

Multiple Choice

Solve the system of equations using substitution.
- $$\left\{ \begin{array} { l } y = x ^ { 2 } - 12 x + 36 \\x + y = 18\end{array} \right.$$

A) x = 2, y = 16; x = 9, y = 9
B) x = 6, y = 12
C) x = 2, y = 20; x = 9, y = 9
D) x = -2, y = 20; x = -9, y = 27