Answer:
square inches.
Step-by-step explanation:
The pizza would have a circular shape so that dividing it into 6 slices implies that there are 6 sectors.
The central angle formed by each sliced pizza = 
= 
Given that the diameter = 18 inches, thus;
radius = 
= 9.0 inches
Since the sliced pizza now has the shape of a sector, then;
the surface area of each large pizza = (θ/360)* 

=
*
*
=
*
*81
= 13.5
square inches
Surface area of each large pizza =
square inches
The surface are of one slice of the large pizza is
square inches.