👉 The hemicircle is a type of circle that has an axis of symmetry and its center coincides with the point where it cuts through the two lines on which it lies. It's also known as a semicircle, and it can be defined using the following formula: hemi = (2r - r²) / 2 where hemi is the area of the hemicircle, r is the radius of the circle, and r² is the square of the radius.