A semi-circle is half of a circle. To find the area of the semi-circle, you should first understand how to find the area of a circle.
The general formula for the area of a circle is: [tex]\pi r^{2}[/tex], so intuitively, the area of a semi-circle is just [tex]\frac{\pi r^{2}}{2}[/tex]
Now, a diameter is twice the length of the radius, so we divide the diameter by 2, to yield the length of the radius, being 1 ft.
Substitute everything into the equation, and we get:
[tex]\frac{\pi 1^{2}}{2}[/tex]
[tex]\frac{\pi}{2}[/tex], which is about 1.5707... ft² ≈ 1.57ft² (nearest hundredth)
