Please solve a and b

9) Consider the solid S in the first octant bounded by z = x and 2x + y +z =15. (20 pts) a) Draw the region in the xz-plane and setup a threefold iterated integral integrating with respect to y first (i.e. dy d* d*) that when evaluated gives the volume of S. b) Draw the region in the xy-plane and setup a threefold iterated integral integrating with respect to z first (i.e. dz d* d*) that when evaluated gives the volume of S. Do not evaluate these iterated integrals. X