Step 1 :\(f(x+h) = -\frac{7}{x+h}\)
Step 2 :\(f(x+h)-f(x) = -\frac{7}{x+h} + \frac{7}{x}\)
Step 3 :\(-\frac{7}{x+h} + \frac{7}{x} = \frac{-7x + 7(x+h)}{x(x+h)} = \frac{7h}{x(x+h)}\)
Step 4 :\(\frac{f(x+h)-f(x)}{h} = \frac{\frac{7h}{x(x+h)}}{h} = \boxed{\frac{7}{x(x+h)}}\)