Simplify: x2+7x+12x2−16\frac{x^2 + 7x + 12}{x^2 - 16}x2−16x2+7x+12
x+3x−4\frac{x+3}{x-4}x−4x+3
x+4x−4\frac{x+4}{x-4}x−4x+4
x−3x−4\frac{x-3}{x-4}x−4x−3
x+1x−1\frac{x+1}{x-1}x−1x+1