Use a graph of the function f(x) = x- 6x 15x + 20 to estimate the local extrema of the function. Use these to determine the intervals on which the function is increasing and decreasing. 40 20 -20- 2 3 A -40- -60 -80+ 7 8 An online service can give you a more accurate answer. Give the coordinates (x, y) of the local maximum: local minimum: Use interval notation to answer these: The function is increasing on: The function is decreasing on: