Let f(x) = 5x2 - 10x. (a) Simplify (3 + h) - f(3) h Algebraically simplify your answer until you have cancelled out the factor of h in the denominator. 5h + 20 (b) Evaluate lim f(3 + h) - f(3) h -0 h If an answer does not exist, enter DNE. X (c) Determine the equation of the line tangent to y = f(x) at x = 3. y