Find the Exact Value Under the Given Conditions Find $\tan ( \alpha + \beta )$

Multiple Choice

Find the exact value under the given conditions.
- $\cos \alpha = - \frac { 5 } { 13 } , \frac { \pi } { 2 } < \alpha < \pi ; \quad \sin \beta = \frac { 15 } { 17 } , \frac { \pi } { 2 } < \alpha < \pi \quad$ Find $\tan ( \alpha + \beta )$

A) $- \frac { 171 } { 221 }$
B) $\frac { 171 } { 140 }$
C) $- \frac { 171 } { 220 }$
D) $\frac { 3 } { 20 }$