Circles - Semi-circles and quarter circles Part 4 (Final Part

The perimeter of a semi-circle can be found by using the equation π x r (squared), which is commonly used to calculate the area of a whole circle:

Area of a semi-circle: 1/2 x π r2

Area of a quarter circle: 1/4 x π x r2

Perimeter of a semi-circle: π x r + 2 x r

Example

A window…