Use Sum and Difference Formulas for Tangents
Find the Exact $$\frac { \tan 70 ^ { \circ } - \tan \left( - 50 ^ { \circ } \right) } { 1 + \tan 70 ^ { \circ } \tan \left( - 50 ^ { \circ } \right) }$$

Multiple Choice

Use Sum and Difference Formulas for Tangents
Find the exact value by using a difference identity.
- $$\frac { \tan 70 ^ { \circ } - \tan \left( - 50 ^ { \circ } \right) } { 1 + \tan 70 ^ { \circ } \tan \left( - 50 ^ { \circ } \right) }$$

A) $- \sqrt { 3 }$
B) $- \frac { \sqrt { 3 } } { 3 }$
C) $- \frac { 1 } { 2 }$
D) $- 2$ .