Semicircle Shape
Find the shaded area of these shapes with perimeters made of semicircles.
Image
![Semicircle Shape Semicircle Shape](/sites/default/files/styles/large/public/thumbnails/content-id-13052-Semicercle%252520Shape%252520Stefania.png?itok=Zp29WmdS)
The figure shows two shapes that fit together exactly.
The outline of each shape is formed by four semicircles of radius 1.
What is the total shaded area?
Drawing on two squares, which will each have side length 2 (equal to the diameter of the semicircles), gives this diagram:
Image
![Semicircle Shape Semicircle Shape](/sites/default/files/styles/large/public/thumbnails/content-id-13052-image4144.png?itok=TIapPdD8)
A total of 3 semicircles have been cut out of the squares, and there are 3 semicircles sticking out of the squares.
So the shaded area is equal to the area of the two squares, which is 2$\times$2 + 2$\times$2 = 8.