Find the Angle ? Between Two Nonvertical Lines $$L _ { 1 }$$

Multiple Choice

Find the angle ? between two nonvertical lines $$L _ { 1 }$$ and $L _ { 2 }$ .The angle ? satisfies the equation? $$\tan \alpha = \left| \frac { m _ { 2 } - m _ { 1 } } { 1 + m _ { 2 } m _ { 1 } } \right|$$ ? where $m _ { 1 }$ and $m _ { 2 }$ are slopes of $L _ { 1 }$ and $L _ { 2 }$ ,respectively.
(Assume that $m _ { 1 } m _ { 2 } \neq 1$ . ) ? $L _ { 1 }$ : 5x - 4y = 5 $L _ { 2 }$ : x + y = 1
?
Round your answer to one decimal place.
?

A) 83.7º
B) 84.7º
C) 85.7º
D) 86.7º
E) 87.7º