Question

perimeter of a semicircle​

Answer 1

Answer:

The perimeter of a semicircle is the sum of the half of the circumference of the circle and diameter. As the perimeter of a circle is 2πr or πd. So, the perimeter of a semicircle is 1/2 (πd) + d or πr + 2r, where r is the radius.

Step-by-step explanation:

Answer 2

Answer:

(i) Perimeter = 28π

(ii) Area = 49π

Step-by-step explanation:

Perimeter of circle is 2 * π * r

Outer Perimeter of a semi-circle is π * radius. (not including the straight cut)

Big circle radius is 14, little circle radius is 7. (half diameter)

Perimeter of shaded area is half of perimeter of big circle and two times half perimeter of little circle

π * 14 + 2*( π * 7) = 28π

Area of a circle is π*r² (r is the radius)

Area of shaded region is area of half-circle minus area of two little half circles

so area of shaded region is [π * (14)² /2] - [π * (7)² / 2] - [π * (7)² / 2] = 49π