Answer:
105.12ft²
Explanation:
Separate the figure into two parts - the 10ftx8ft rectangle, and the semicircle with the 8ft diameter.
1. Area of rectangle = 10ftx8ft = 80ft²
2. The area of a whole circle is found with the formula A=πr², where r is the radius. Since the diameter is twice the radius, r=d/2=8f/2=4ft.
So the area of a whole circle with an 8ft diameter is A=πr²=π(4ft)²=16πft². But we only have a semicircle, so divide by 2:
16πft²/2=8πft²≈8(3.14)ft²=25.12ft²
3. Add the two areas together: (80+25.12)ft²=105.12ft²