Find the indicated derivative. Then find an equation of the tangent line at the indicated point on the graph of the function. dy 3 if y = (x,y) = (9,3) dx VX- B dy dx (Type an exact answer, using radicals as needed.) The equation of the tangent line at the point (9,3) is y =f(z) - f(x) Use the formula f'(x) = lim Z-X to find the derivative of the following function. Z=X f(x) = 3x2- x+5 f' (x) =