3 For f(x)=2x-16x + 5 find the following. (A) f'(x) (B) The slope of the graph of f at x = -2 (C) The equation of the tangent line at x = -2 (D) The value(s) of x where the tangent line is horizontal (A) f'(x) = (B) At x = -2, the slope of the graph of f is (C) At x = -2, the equation of the tangent line is y = (D) The tangent line is horizontal at x = (Use a comma to separate answers as needed.)