Suppose that f(x) = 12x2 + 6x. Find: (A) f' (a) = (B) The slope of the graph of f(x) at a = 2 and a = 3. Slope at X = 2: Slope at X = 3: (C) An equation for the tangent lines at x = 2 and x = 3. Tangent line at x = 2: y = Tangent line at x = 3: y (D) List all values of a where the tangent line is horizontal. Value(s) of x =