Find the area and perimeter of the shape below and tell me what you find.

The circumference of the first picture is the curve length of a rectangle plus a semicircle with a radius of width, where the length is twice the width, so it can be concluded that the circumference is equal to 2 times the width and π times the width is equal to 5. 14 times the width.

Area = area of rectangle-area of semicircle =2r? _πr？ ÷2=0.43r？

The second picture (where the radius of the circle is half the side length of the square, a=2r)

bellyband

Perimeter = 2X4 = 8R Perimeter = 2π Rb = 2π RC = 2R2x+2π r = 4r+2π r =10,28r

zone

A=B=C=2rx2r_πr？ =4r？ -πr？ =0.86r？

find

The shaded area in the first picture is: rectangular area-semi-circular area.

In the second picture, the area of the blank part is equal to the area of a circle, so in the second picture, the areas of the three shaded parts are equal, and they are all square areas-the area of a circle. .

The perimeters are all unequal.