Build a measured area from nonoverlapping shapes. Dimensions are in feet; a circle uses radius. Subtract only exclusions inside your measured sections.
Check the method
Rectangle = length × width; triangle = base × perpendicular height ÷ 2; circle = π × radius². Net area = included sections − exclusions. A 12 × 8 rectangle plus an 8 × 6 triangle minus a 2 × 3 exclusion is 114 sq ft.
Use your area for topsoil · Use your area for mulch