Question

$\frac{4}{x + 4} - \frac{x}{x - 4}$

Answer 1

$\frac{4}{x + 4} - \frac{x}{x - 4} \\ \\ \frac{4(x - 4) - x \times (x + 4)}{(x + 4) \times (x - 4)} \\ \\ \frac{4x - 16 - x {}^{2} - 4x}{x {}^{2} - 16} \\ \\ \frac{ - 16 - x {}^{2} }{x {}^{2} - 16} \\ \\ - \frac{16 + x {}^{2} }{x {}^{2} - 16}$