Simplify: x2−7x+12x2−16\dfrac{x^2 - 7x + 12}{x^2 - 16}x2−16x2−7x+12 (assume x≠±4x \neq \pm 4x=±4).
x−3x+4\dfrac{x - 3}{x + 4}x+4x−3
x−3x−4\dfrac{x - 3}{x - 4}x−4x−3
x+3x+4\dfrac{x + 3}{x + 4}x+4x+3
x−4x+4\dfrac{x - 4}{x + 4}x+4x−4