a semicircle has an area of 76.97 km. Find its radius
The formula for the area of a circle is: A = πr².
A semicircle is half of a circle, so its formula is: A = ½πr².
---> 76.97 = ½πr²
Multiply by 2: 153.94 = πr²
Now, divide by pi, and find the square root ...