R(-1; 9) is the turning point of the graph: f(x) = ax² + bx + c. P and Q are the x-intercepts of f. TV is a straight line parallel to the y-axis. The graph of g(x) = x+4 has an x-intercept at P. S is a point of intersection of f and g. P R(-1;9) S 6.1 6.2 6.3 6.4 6.5 Determine the coordinates of P. Hence, or otherwise, write down the coordinates of Q. Calculate the average gradient between P and R. Show that for f, a = -1, b = -2 and c = 8. Show ALL your working. Calculate the coordinates of S, the point of intersection of fand g. 6.6 Determine the maximum length of TV between the points P and S. (5) (5) (6) ཕྱི ཕྱི ཧེ ཁྱེÊ D (2)​