Question

What is the quotient of x+4÷x2-16 over x2-1÷x2+3x-28

Answer 1

$\frac{\frac{x+4}{x^2-16}}{\frac{x^2-1}{x^2+3x-28}}\\=\frac{x+4}{(x+4)(x-4)}\times\frac{(x-4)(x+7)}{(x-1)(x+1)}\\=\frac{x+7}{x^2-1}$