Tomamos como el límite
$$\lim_{x \to -7^+}\left(\frac{5 x + 6}{4 x + \left(x^{2} + 4\right)}\right)$$
cambiamos
$$\lim_{x \to -7^+}\left(\frac{5 x + 6}{4 x + \left(x^{2} + 4\right)}\right)$$
=
$$\lim_{x \to -7^+}\left(\frac{5 x + 6}{\left(x + 2\right)^{2}}\right)$$
=
$$\lim_{x \to -7^+}\left(\frac{5 x + 6}{\left(x + 2\right)^{2}}\right) = $$
$$\frac{\left(-7\right) 5 + 6}{\left(-7 + 2\right)^{2}} = $$
= -29/25
Entonces la respuesta definitiva es:
$$\lim_{x \to -7^+}\left(\frac{5 x + 6}{4 x + \left(x^{2} + 4\right)}\right) = - \frac{29}{25}$$