We have indeterminateness of type
0/0,
i.e. limit for the numerator is
$$\lim_{x \to 2^+}\left(x^{2} - 4\right) = 0$$
and limit for the denominator is
$$\lim_{x \to 2^+}\left(3 - \sqrt{x + 7}\right) = 0$$
Let's take derivatives of the numerator and denominator until we eliminate indeterninateness.
$$\lim_{x \to 2^+}\left(\frac{x^{2} - 4}{3 - \sqrt{x + 7}}\right)$$
=
$$\lim_{x \to 2^+}\left(\frac{\frac{d}{d x} \left(x^{2} - 4\right)}{\frac{d}{d x} \left(3 - \sqrt{x + 7}\right)}\right)$$
=
$$\lim_{x \to 2^+}\left(- 4 x \sqrt{x + 7}\right)$$
=
$$\lim_{x \to 2^+} -24$$
=
$$\lim_{x \to 2^+} -24$$
=
$$-24$$
It can be seen that we have applied Lopital's rule (we have taken derivatives with respect to the numerator and denominator) 1 time(s)