Solve the System for X and Y Using Cramerʹs Rule $$\begin{array} { l } a ^ { 2 } x + b ^ { 2 } y = a ^ { 2 } \\a x + b y = b\end{array}$$

Solve the system for x and y using Cramerʹs rule. Assume a and b are nonzero constants.
- $$\begin{array} { l } a ^ { 2 } x + b ^ { 2 } y = a ^ { 2 } \\a x + b y = b\end{array}$$

A) $\left\{ \left( \frac { a + b } { a } , \frac { a } { b } \right) \right\}$
B) $\left\{ \left( \frac { a - b } { a } , - \frac { a } { b } \right) \right\}$
C) $\left\{ \left( \frac { a + b } { a } , \frac { b - a } { b } \right) \right\}$
D) $\left\{ \left( \frac { a + b } { a } , - \frac { a } { b } \right) \right\}$