Answer:
(π/2)r²
Step-by-step explanation:
The formula for the area of a circle of radius r is A = πr². Thus, the formula for the area of a semicircle of the same radius is A/2 = (π/2)r². For a numerical answer you'll need to specify the radius.
Note: π = Greek letter pi; "pie" is a dessert, inappropriate here. :)
