The volume of clay used to build a cylindrical pillar with a height of 9 centimeters is 324π cubic centimeters. the area of the base of the pillar π square centimeters.

Area=height times base (for some prisms including cylinders)
vcylinder=hpir²
h=height
therefor pir²=base area
vcylinder=height times aeraofbase

 

given
h=9
v=324pi
324pi=9(basearea)
divide both sides by 9
36pi=areabase

the area of the base is 36pi square cm (put 36 in the blank since the pi is already there)

The volume of a cylinder is V = pi*r^2*h.

Here 324*pi cc = (pi*r^2)*h, where h = 9 cm
                                                                     324*pi cc
Thus,    the area of the base,  (pi*r^2) , is
                                                                         9 cm, which simplifies to

base area = 36π cm^2