Given f (x) = x^2 + 4x and g(x) = 9 - x^2, find f +g, f - g, fg, and f/g Enclose numerators and denominators in parentheses. For example, (a - b)/(1+n). (f +g)(x) = ?
(f - g)(x) = ?
fg(x) = ?
f/g(x) = ?​