Find a Formula for the Slope of the Graph Of f

Multiple Choice

Find a formula for the slope of the graph of $f$ at the point $( x , f ( x ) )$ .Then use it to find the slope at the given point. $f ( x ) = \frac { 1 } { x + 6 } , \quad \left( - 2 , \frac { 1 } { 4 } \right)$

A) $\begin{array} { l } m = \frac { 1 } { ( x + 6 ) ^ { 2 } } \\\text { At } \left( - 2 , \frac { 1 } { 4 } \right) , m = - \frac { 1 } { 16 }\end{array}$
B) $\begin{array} { l } m = \frac { 1 } { ( x + 6 ) ^ { 2 } } \\\text { At } \left( - 2 , \frac { 1 } { 4 } \right) , m = \frac { 1 } { 16 }\end{array}$
C) $\begin{array} { l } m = - \frac { 1 } { ( x + 6 ) ^ { 2 } } \\\text { At } \left( - 2 , \frac { 1 } { 4 } \right) , m = \frac { 1 } { 16 }\end{array}$
D) $\begin{array} { l } m = - \frac { 1 } { ( x + 6 ) ^ { 2 } } \\\text { At } \left( - 2 , \frac { 1 } { 4 } \right) , m = - \frac { 1 } { 16 }\end{array}$
E) $\begin{array} { l } m = - \frac { 1 } { ( x + 6 ) } \\\text { At } \left( - 2 , \frac { 1 } { 4 } \right) , m = - \frac { 1 } { 16 }\end{array}$