Find the limit$.($If an answer does not exist, enter DNE.$)$

$\underset{x7}{lim}\frac{x-7}{x^2-49}$

STEP $1$: Factor the denorfhinator.

STEP $2$: Simplify.

$\underset{x7}{lim}\frac{1}{x+}$

STEP $3$: Use your result from Step $2$ to find the limit$.$

$\underset{x7}{lim}\frac{x-7}{x^2-49}=$

$$