Solve the System of Equations by the Addition Method $\left\{ \begin{array} { l } x + y = 23 \\x - y = 15\end{array} \right.$

Multiple Choice

Solve the system of equations by the addition method.
- $\left\{ \begin{array} { l } x + y = 23 \\x - y = 15\end{array} \right.$

A) no solution
B) $( 19,4 )$
C) $( 4,19 )$
D) $\left( \frac { 23 } { 2 } , \frac { 15 } { 2 } \right)$