Question 651494
<img src="http://latex.codecogs.com/gif.latex?\large \large \lim_{x\to4} \frac{x-4}{x^2-16}" />


<img src="http://latex.codecogs.com/gif.latex?\large \lim_{x\to4} \large \lim_{x\to4} \frac{x-4}{(x-4)(x+4)}" />


<img src="http://latex.codecogs.com/gif.latex?\large \large \lim_{x\to4} \frac{1}{x+4}" />


So 


<img src="http://latex.codecogs.com/gif.latex?\large \large \lim_{x\to4} \frac{x-4}{x^2-16} = \lim_{x\to4} \frac{1}{x+4}" />


<img src="http://latex.codecogs.com/gif.latex?\large \large \lim_{x\to4} \frac{x-4}{x^2-16} =\frac{1}{4+4}" />


<img src="http://latex.codecogs.com/gif.latex?\large \large \lim_{x\to4} \frac{x-4}{x^2-16} = \frac{1}{8}" />